Peer Revenue Impact factor: volatile

Papers

Fresh from arXiv, typeset properly. Highlighted words trade on the market.

Physics

Watch Physics

Tuesday 14 July

Soft Condensed Matter

Fundamental Relation between Conductance of Biomolecules and the Fukui Function

Gabor Vattay

We derive the finite-temperature conductance of a molecule coupled to metallic leads using open-system time-dependent density functional theory (TDDFT). Tracing out the phonon bath via Wick's theorem yields an exchange-symmetric collision integral that preserves Pauli exclusion. When internal thermalization is faster than lead escape, as holds in proteins with multifractal orbitals at the Anderson transition, the exchange-correlation kernel projects out of the slow Liouvillian mode, making conductance directly proportional to the finite-temperature Fukui function of conceptual DFT.
Read the full abstract

Plasma Physics

Structural Requirements for Ion-Acoustic Double Layers: A Parametric Perturbation Analysis of the Maxwellian Limit

Hamdi M. Abdelhamid, Abeer A. Mahmoud and Naoki Sato

Standard Maxwellian plasmas exhibit a mathematical rigidity, possessing insufficient degrees of freedom to support electrostatic double layers (DLs) and yielding only soliton solutions. This study investigates the hypothesis that the formation of DLs is a generic consequence of breaking this structural rigidity through parametric perturbation. By introducing two independent continuous control parameters, $\delta_1$ and $\delta_2$, into the electron distribution, we demonstrate that DLs are a structural property of any plasma model that relaxes the strict Maxwellian constraint. Through a Gardner small-amplitude expansion, we analytically prove that a perturbation must modify both the quadratic and cubic density coefficients to decouple the nonlinear structure and generate physical, supersonic double layers, deriving small-amplitude acoustic-limit threshold conditions of $\delta_1 > 1$ and $\delta_2 > 7/3$. We show that these theoretical boundaries broaden for large-amplitude, nonlinear structures. By mapping the exact existence regions of DLs in phase space, we demonstrate how higher-order terms relax the weak-amplitude limits, confirming that the Maxwellian state represents a singular point where the DL solution collapses.
Read the full abstract

Quantum Physics

Precision quantum simulation of magnon spectra and interactions

Trond I. Andersen, Nikita Astrakhantsev, Jeronimo Martinez et al. (+329 more)

Quantum simulation promises to advance materials discovery by accurately simulating complex states of matter, their microscopic excitations, and macroscopic response functions. The central challenge in resolving the underlying interacting dynamics is to combine high-fidelity evolution with the sophisticated control necessary to manipulate individual quasi-particles in quantum many-body states. Here, we report on high-precision simulation of both linear and non-linear response functions in a 2D XY spin-1/2 magnet using an analog-digital superconducting processor of up to 97 qubits. By interleaving digital gates with analog evolution precisely characterized via Hamiltonian learning, we selectively excite magnons at tunable energy densities. Measuring first the linear magnon response – a central probe in neutron-scattering experiments – we extract temperature-dependent spectra and lifetimes. Our results reveal stark variations in magnon decay rates across the Brillouin zone, with enhancement near van Hove singularities and suppression for edge-localized modes. Next, we perform a suite of nonlinear measurements, including the study of self-scattering mechanisms, as well as pump-probe spectroscopy to directly characterize the magnon interactions. While matrix-product state simulations capture the dynamics well in either small systems or at low temperatures, their predictions become inaccurate away from these limits. This work demonstrates precise simulation of the interacting dynamics in quantum magnets, and provides key insights into quasi-particles and their microscopic scattering mechanisms.
Read the full abstract

All authors Trond I. Andersen, Nikita Astrakhantsev, Jeronimo Martinez, Will Morong, Johannes Motruk, Dario Rossi, Brayden Ware, Bryce Kobrin, Weijie Wu, Elizabeth Bennewitz, Manuel Rudolph, Tom Westerhout, Amira Abbas, Rajeev Acharya, Laleh Aghababaie Beni, Ross Alcaraz, Sayra Alcaraz, Markus Ansmann, Frank Arute, Kunal Arya, Walt Askew, Juan Atalaya, Christopher Ayala, Ryan Babbush, Brian Ballard, Joseph Bardin, Hector Bates, Andreas Bengtsson, Majid Bigdeli Karimi, Alexander Bilmes, Simon Bilodeau, Felix Borjans, Alexandre Bourassa, Jenna Bovaird, Dylan Bowers, Leon Brill, Peter Brooks, Michael Broughton, David Browne, Brett Buchea, Bob Buckley, Tim Burger, Brian Burkett, Jamal Busnaina, Nicholas Bushnell, Jonas Bylander, Anthony Cabrera, Juan Campero, Hung-Shen Chang, Silas Chen, Zijun Chen, Ben Chiaro, Liang-Ying Chih, Agnetta Cleland, Bryan Cochrane, Matt Cockrell, Josh Cogan, Paul Conner, Tom Connolly, Harold Cook, Rodrigo Cortinas, William Courtney, Alexander Crook, Benjamin Curtin, Adam Dally, Sayan Das, Martin Damyanov, Dripto Debroy, Himadri Dey, Stijn de Graaf, Laura De Lorenzo, Sean Demura, Lucia De Rose, Agustin Di Paolo, Leon Ding, Howard Dobbs, Paul Donohoe, Ebru Dogan, Ilya Drozdov, Andrew Dunsworth, Rasmus Edholm, Valerie Ehimhen, Alec Eickbusch, Aviv Elbag, Lior Ella, Mahmoud Elzouka, David Enriquez, Catherine Erickson, Lara Faoro, Vinicius Ferreira, Marcos Flores, Leslie Flores Burgos, Sam Fontes, Ebrahim Forati, Jeremiah Ford, Brooks Foxen, Masaya Fukami, Alan Fung, Lenny Fuste, Suhas Ganjam, Gonzalo Garcia, Christopher Garrick, Robert Gasca, Helge Gehring, Robert Geiger, Élie Genois, William Giang, Dar Gilboa, James Goeders, Edward Gonzales, Raja Gosula, Alejandro Grajales Dau, Dietrich Graumann, Joel Grebel, Alex Greene, Jonathan Gross, Jose Guerrero, Tan Ha., Steve Habegger, Tanner Hadick, Ali Hadjikhani, Michael Hamilton, Monica Hansen, Matthew Harrigan, Sean Harrington, Jeanne Hartshorn, Stephen Heslin, Paula Heu, Oscar Higgott, Reno Hiltermann, Jeremy Hilton, Hsin-Yuan Huang, Michael Hucka, Christopher Hudspeth, Ashley Huff, William Huggins, Aditya Jayaraman, Evan Jeffrey, Shaun Jevons, Zhang Jiang, Xiaoxuan Jin, Cody Jones, Chaitali Joshi, Kelsey Josund, Pavol Juhas, Andreas Kabel, Bharath Kannan, Hui Kang, Kiseo Kang, Amir Karamlou, Ryan Kaufman, Tanuj Khattar, Mostafa Khezri, Seon Kim, Paul Klimov, Can Knaut, Alexander Korotkov, Fedor Kostritsa, John Mark Kreikebaum, Ryuho Kudo, Arun Kumar, Ben Kueffler, Vladislav Kurilovich, Vitali Kutsko, Nathan Lacroix, Tiano Lange-Dei, Brandon Langley, Pavel Laptev, Kim-Ming Lau, Emma Leavell, Loïck Le Guevel, Justin Ledford, Joy Lee, Kenny Lee, Brian Lester, Wendy Leung, Matthew Lloyd, Lily Li, Wing Li, Ming Li, Alexander Lill, Mike Lindmark, William Livingston, Aditya Locharla, Erik Lucero, Daniel Lundahl, Aaron Lunt, Sid Madhuk, Donald Macaskill, Aniket Maiti, Ashley Maloney, Salvatore Mandra, Leigh Martin, Orion Martin, Eric Mascot, Paul Masih Das, Anselme Massimino, Melvin Mathews, Cameron Maxfield, Jarrod McClean, Matthew McEwen, Seneca Meeks, Anthony Megrant, Tim Menke, Kevin Miao, Zlatko Minev, Reza Molavi, Sebastian Molina, Shirin Montazeri, Akira Nakamura, Charles Neill, Konstantin Nesterov, Michael Newman, Roselle Ngaloy, Anthony Nguyen, Murray Nguyen, Chia-Hung Ni, Murphy Niu, Nicholas Noll, Sergey Novikov, Logan Oas, Ricky Oliver, Will Oliver, Raymond Orosco, Kristoffer Ottosson, Alice Pagano, Manan Patel, Sherman Peek, David Peterson, Alex Pizzuto, Thomas Plumb-Reyes, Elias Portoles, Rebecca Potter, Orion Pritchard, Sam Probst, Michael Qian, Chris Quintana, Matthew Rakher, Arpit Ranadive, Ganesh Ramachandran, Armin Razavi, Matthew Reagor, Rachel Resnick, David Rhodes, Daniel Riley, Gabrielle Roberts, Roberto Rodriguez, Emma Ropes, Eliott Rosenberg, Emma Rosenfeld, Dario Rosenstock, Elizabeth Rossi, Pedram Roushan, David Rower, Robert Salazar, Kannan Sankaragomathi, Murat Sarihan, Kevin Satzinger, Max Schaefer, Sebastian Schroeder, Henry Schurkus, Aria Shahingohar, Michael Shearn, Aaron Shorter, Shvarts Vladimir, Vlad Sivak, Spencer Small, W. Clarke Smith, David Sobel, Barrett Spells, Sofia Springer, George Sterling, Scott Stonemeyer, John Su, Jordan Suchard, Youngkyu Sung, Aaron Szasz, Alex Sztein, Tomoyuki Tanaka, Madeline Taylor, Jothi Thiruraman, Douglas Thor, Brandur Thorgrimsson, Dogan Timucin, Eifu Tomita, Alfredo Torres, M. Mert Torunbalci, Hao Tran, Abeer Vaishnav, Justin Vargas, Gopinath Vasalamarri, Sergey Vdovichev, Guifre Vidal, Benjamin Villalonga, Meghan Voorhees, Steven Waltman, Jonathan Waltz, Shannon Wang, Danni Wang, James Watson, Yonghua Wei, Travis Weidel, Theodore White, Kristi Wong, Bryan Woo, Christopher Wood, Maddy Woodson, Cheng Xing, Z. Jamie Yao, Ping Yeh, Bicheng Ying, Juhwan Yoo, Noureldin Yosri, Elliot Young, Grayson Young, Adam Zalcman, Ran Zhang, Yaxing Zhang, Yiqing Zhou, Ningfeng Zhu, Nicholas Zobrist, Zhenjie Zou, Sergio Boixo, Yu Chen, Julian Kelly, Hartmut Neven, Vadim Smelyanskiy, Dvir Kafri, L. B. Ioffe, Kostyantyn Kechedzhi, Xiao Mi, Dmitry Abanin

Superconductivity

Theoretical prediction of structural stability and superconductivity in T-hexagonal molybdenum dihydrides Monolayer

Jakkapat Seeyangnok and Udomsilp Pinsook

The realization of ambient-pressure, high-temperature superconductivity in hydrogen-rich materials remains a major pursuit in condensed-matter physics. While bulk hydrides require extreme pressures to stabilize, two-dimensional (2D) transition-metal hydrides offer a promising alternative to bypass these compression constraints. In this work, we investigate the structural stability, electronic properties, and phonon-mediated superconductivity of a hexagonal molybdenum dihydride (MoH2) monolayer using first-principles calculations. Total-energy evaluations reveal that the octahedral T-phase is energetically more favorable than the previously reported trigonal prismatic H-phase by 0.198 eV, establishing the T-phase as the true ground-state configuration. Consequently, we systematically evaluate the lattice dynamics and superconducting properties of this ground-state T-MoH2 monolayer within the frameworks of density functional perturbation theory (DFPT) and the anisotropic Migdal-Eliashberg formalism. The transition metal-hydrogen vibrational networks induce strong electron-phonon coupling (EPC), yielding an integrated coupling parameter of \lambda = 1.04. Solving the anisotropic Eliashberg equations predicts a conventional superconducting transition temperature (Tc of 14.4K) at ambient pressure, characterized by a moderately gap distribution (\Delta = 2.07-3.01meV at 5.0 K). Our findings highlight the T-MoH2 monolayer as a structurally, mechanically, and thermally stable platform for exploring low-dimensional conventional superconductivity under ambient conditions.
Read the full abstract

Optics

Unveiling Structured Optical Coherence in Nonlinear Optics

Zihao Pang and Ady Arie

Nonlinear optical interactions are typically driven by coherent sources. Recently, however, incoherent sources have also been shown to offer new opportunities in nonlinear optics. Here we study the effects of the source incoherence in second harmonic generation. We derive and experimentally validate an analytic expression for the far-field coherence function at the second harmonic frequency, which is a generalization of the well-known van Cittert-Zernike theorem. Unlike the linear optics case, here the results depend not only on the source spatial distribution, but also on the nonlinear structure of the crystal. We further show, by performing Young's double-slit measurement, that the coherence at the second harmonic increases as the light propagates inside the nonlinear crystal. Our results establish nonlinearity as a degree of freedom for optical coherence, opening a new research area at the interface of statistical optics and nonlinear optics.
Read the full abstract

Mesoscale and Nanoscale Physics

Electronic properties and topological aspects of graphene nanohelicoids

Xiaoqian Liu, Arsen Herasymchuk, Yaroslav Zhumagulov et al. (+1 more)

We introduce graphene nanohelicoids, geometric analogs of graphene nanoribbons, in which the honeycomb lattice is embedded on a helicoidal surface. Starting from the three-dimensional helical structure, we construct effective one-dimensional lattice models with band structures characterized by a momentum-shifted particle-hole relation $E_v(k)=-E_c(k+\pi)$ that reflects an antichiral symmetry arising from the nonsymmorphic symmetry. A systematic investigation of graphene nanohelicoids using the tight-binding approximation reveals a number of trends upon varying width and edge orientation, for instance, alternating transitions between semiconducting and metallic regimes. As the structure width varies, the band gap periodically closes and reopens, accompanied by an alternating Zak phase that switches between trivial and nontrivial. Using an analytic tight-binding model with a continuous deformation of the graphene nanohelicoids, we explain the origin of width- and termination-dependent band inversion and alternating Zak phase, and derive the relationship between the termination-resolved index and the sublattice symmetry operator in one-dimensional nonsymmorphic systems.
Read the full abstract

All authors Xiaoqian Liu, Arsen Herasymchuk, Yaroslav Zhumagulov, Oleg V. Yazyev

Quantum Physics

A Measurement Plane for Quantum Networking

Abderrahim Amlou, Amar Abane, Anouar Rahmouni et al. (+6 more)

Quantum networking testbeds lack a distinct plane for coordinating distributed measurements and collecting experimental data across heterogeneous devices. To address this gap, we present the Measurement Plane, a dedicated plane that complements the data, control, and management planes rather than replacing or extending their pipelines. The contribution is presented as a distributed framework that organizes measurement functions into four layers: application, experiment coordination, capability, and resource agents. Our design separates user workflows from device-specific control. We implemented the framework as containerized microservices connected through publish–subscribe messaging, and validated it on a two-node quantum networking setup connected by an optical network. The framework successfully coordinated remote nodes to execute coincidence measurement and polarization entanglement distribution experiments with visibility interference of up to 98 percent. This evaluation demonstrated the effectiveness of the framework for supporting complex, distributed quantum experiments, enabling online measurement and feedback, and significantly reducing manual configuration and execution effort.
Read the full abstract

All authors Abderrahim Amlou, Amar Abane, Anouar Rahmouni, Mheni Merzouki, Abdella Battou, Ahmed Lbath, Ya-Shian Li-Baboud, Oliver Slattery, Thomas Gerrits

Optics

Engineering Nanophotonic Modes via the Radiation Continuum

Francesco Pisani, Baptiste Fix, Thomas Krieguer et al. (+5 more)

We demonstrate, experimentally and theoretically, a universal mechanism for combining nanophotonic modes relying on radiative-loss-mediated couplings. For the case of two modes this mechanism leads to a BIC-type phenomenon characterized by the emergence of a high-quality factor subradiant mode. This mode is experimentally observed in the mid-infrared range, in arrays of double-metal patch antennas where the radiation loss rates are controlled by the geometry of the system. As the mechanism described here is independent of the specific nature or number of the interacting modes, it can be used to combine physically different resonating structures, without requiring fine symmetry tuning or specific modal configurations, opening new opportunities for resonance-based nanophotonic devices.
Read the full abstract

All authors Francesco Pisani, Baptiste Fix, Thomas Krieguer, Alexis Jouan, Cheryl Feuillet-Palma, Isabelle Sagnes, Patrick Bouchon, Yanko Todorov

Optics

Exactly Solvable Diffraction-Grating Scattering Problems for TE and TM waves

Farhang Loran and Ali Mostafazadeh

In J.~Phys.~A 31, 3493 (1998), Berry provides an analytic solution of the problem of determining the diffracted beam intensities for atoms incident upon a grating given by the potential, $v(x,y):=iV_0(e^{i\mathfrak{K}\,y}-1)$ for $0\leq x\leq\ell$ and $v(x,y):=0$ otherwise, where $V_0, \mathfrak{K}$, and $\ell$ are positive real parameters. This result, which relies on the paraxial approximation, readily applies to the diffraction of transverse electric (TE) waves by the nonmagnetic optical grating given by the relative permittivity, $\hat\varepsilon(x,y):=1-v(x,y)/k^2$, where $k$ is the incident wavenumber. We show that Berry's grating belongs to a larger class of possibly magnetic diffraction gratings whose scattering problem for both TE and transverse magnetic (TM) waves are exactly solvable. Our analysis makes use of a recently developed dynamical formulation of stationary scattering that is based on the idea of mapping the scattering problem to the quantum dynamics generated by an effective non-Hermitian Hamiltonian operator. {We use this formulation to derive explicit analytic expressions for the diffracted beam amplitudes that are valid beyond paraxial approximation.} As a concrete example, we offer the exact solution of the scattering problem for TE and TM waves incident upon a generalization of Berry's grating.
Read the full abstract

Cosmology and Nongalactic Astrophysics

The $H_0$ world cup. II. A comprehensive competition between proposed Hubble tension solutions

Nils Schöneberg, Vivian Poulin, Angelo G. Ferrari et al. (+6 more)

Cosmology stands at a crossroads. The Hubble tension has reached a nominal significance above $7\sigma$, while analyses combining DESI BAO and Type Ia supernova data show emerging hints of departures from $\Lambda$CDM. Meanwhile, high-precision CMB measurements from ACT and SPT enable a timely and more stringent reassessment of proposed solutions to the tension. In this paper, we revisit the $H_0$ Olympics, a systematic contest comparing proposed alternatives to $\Lambda$CDM using common datasets, likelihoods, and statistical criteria. In this updated edition, the $H_0$ World Cup, we subject fourteen representative solutions to a common analysis of current CMB, BAO, and SN data. The contenders span four broad mechanisms: late-time modifications of the expansion history, modified recombination, additional pre-recombination radiation, and early non-radiative energy injection. Relative to the original analysis, the present competition includes models and mechanisms proposed in the intervening years and evaluates all contenders using both Bayesian and Frequentist tests of tension and model performance, letting the neutrino mass sum vary. We further test if late-time extensions through curvature or the Chevallier-Polarski-Linder (CPL) dark energy parametrization can aid the success of the models. Finally, we subject the leading contenders to dedicated robustness tests involving alternative CMB likelihoods and multipole cuts, supernova samples, large-scale-structure information, and big-bang nucleosynthesis constraints. This framework assesses both the ability of each mechanism to ease the Hubble tension and the robustness of our conclusions to datasets and analysis choices.
Read the full abstract

All authors Nils Schöneberg, Vivian Poulin, Angelo G. Ferrari, Fabio Finelli, Julien Lesgourgues, Luca Morelli, Markus R. Mosbech, Ravi Kumar Sharma, Théo Simon

Cosmology and Nongalactic Astrophysics

The $H_0$ World Cup. I. Summary of the baseline group stage results

Nils Schöneberg, Vivian Poulin, Angelo G. Ferrari et al. (+6 more)

The Hubble tension has reached a nominal significance above $7\sigma$, while new high-precision measurements of the cosmic microwave background (CMB) and baryon acoustic oscillations (BAO) sharpen the test of proposed solutions. Using a common framework, we compare fourteen representative alternatives to the standard $\Lambda$ Cold Dark Matter ($\Lambda$CDM) model in light of up-to-date CMB, BAO and supernovae data to gauge their ability to resolve the tension. The models span late-time modifications, modified recombination, and exotic pre-recombination expansion histories driven by additional radiation or a localized dark energy injection. We evaluate each proposal with complementary frequentist and Bayesian measures of the residual calibration tension and of the improvement in the joint fit. Both approaches identify the same broad hierarchy. Early dark energy and early modified gravity models perform best, shifting the $H_0$ inference without local measurement priors toward $70\,\mathrm{km\,s^{-1}\,Mpc^{-1}}$ and reducing the residual discrepancy with SH0ES to approximately $2.5-3.6\sigma$, depending on the model and statistic, while receiving strong support over $\Lambda$CDM in the combined fit. Varying the electron mass at recombination yields an intermediate improvement, whereas the enhanced-radiation and late-time scenarios do not improve over $\Lambda$CDM. This Letter summarizes the group stage of the competition; in a companion paper (Paper II) we present the results of an exhaustive set of analyses and assess their robustness to variations in modeling assumptions and datasets.
Read the full abstract

All authors Nils Schöneberg, Vivian Poulin, Angelo G. Ferrari, Fabio Finelli, Julien Lesgourgues, Luca Morelli, Markus R. Mosbech, Ravi Kumar Sharma, Théo Simon

General Relativity and Quantum Cosmology

Precision Ringdown Measurements of Binary Black Hole Remnants

Achal Kumar, Poulami Dutta Roy, Marek J. Szczepańczyk et al. (+1 more)

The ringdown gravitational wave from a binary black hole (BBH) merger is a superposition of quasi-normal modes (QNMs) of the remnant black hole. In general relativity (GR), QNMs are damped harmonic oscillations with frequencies and damping times uniquely determined by the remnant's mass and spin. The measurement of the ringdown modes and performing black hole spectroscopy provides a tool to test the validity of GR. In this work, we present RingCWB, a ringdown analysis method based on coherent WaveBurst (cWB), an unmodeled pipeline for the detection and reconstruction of gravitational-wave signals. This method yields tighter constraints on the QNM frequency and damping time than previous measurements. The improved precision results from the noise reduction achieved by the cWB reconstruction and the enhanced ringdown analysis, which probes the remnant properties at earlier times, closer to the merger. We have analysed publicly available binary black hole (BBH) detections from the third Gravitational-Wave Transient Catalog (GWTC-3). For all events considered, the measured frequency and damping time of the dominant $(l,m)=(2,2)$ mode are found to be consistent with the predictions of GR. A combined analysis further strengthens these constraints, yielding fractional deviations in frequency $\delta f_{220} = -0.005_{-0.028}^{+0.028}$ and damping time $\delta\tau_{220} = 0.032_{-0.090}^{+0.108}$, consistent with zero within the quoted uncertainties.
Read the full abstract

All authors Achal Kumar, Poulami Dutta Roy, Marek J. Szczepańczyk, Sergey Klimenko

Astrophysics of Galaxies

COSMOS2025: A Machine Learning Census of Massive Quiescent Galaxies at $2.5 < \text{z} < 5$

Vahid Asadi, Hosein Haghi and Akram Hasani Zonoozi

The existence of massive quiescent galaxies at high redshifts ($ \text{z} \gtrsim 2$) strongly constrains the rapid quenching mechanisms in galaxy evolution models. We present a machine learning framework to identify massive ($\log(\text{M}_*/\text{M}_\odot) > 9.5$) quiescent galaxies at $2.5 < \text{z} < 5$ in the COSMOS2025 catalog. We train a CatBoostClassifier on mock photometry from the Santa Cruz semi-analytic models (SAMs), incorporating key JWST NIRCam bands and realistic noise to transfer the SAM-derived quiescent label (based on specific star-formation rate) to the observational space. When validated against the SAM ground truth, our classifier achieves a significantly higher recall (completeness) of 78% (compared to 53% for spectral energy distribution (SED)-fitting), while maintaining a high purity of 82%. Applied to the COSMOS2025 sample, and assuming the SAM definition of quiescence transfers to the real Universe, the model identifies 1111 quiescent candidates, a population 2.6 times larger than the 427 candidates identified via the catalog's simple SED-fitting configuration. Under the SAM definition of quiescence, this consistent pattern of high purity but poor completeness suggests that the SED-fitting methods, constrained by simplified parametric star-formation histories, may miss a significant fraction of the quiescent population, likely galaxies in crucial transitional evolutionary stages. The trained classifier and classified COSMOS2025 sample are publicly available.
Read the full abstract

Nuclear Theory

Neural-Accelerated Bayesian Calibration of Chiral Mean-Field Models to Nuclear Saturation and Vacuum Properties

Isaac Legred, Mateus Reinke Pelicer, Veronica Dexheimer et al. (+2 more)

Chiral models of nuclear interactions provide approximate, phenomenological descriptions of dense matter that respect the symmetries of quantum chromodynamics. Their Lagrangian parameters, however, are difficult to calibrate because these models are not controlled effective theories. Furthermore, repeated model evaluations are computationally expensive, and most parameter choices fail to reproduce acceptable saturation properties or hadron masses in vacuum. To address this, we develop a Bayesian inference framework to identify parameter regions consistent with nuclear saturation properties and vacuum experimental constraints. We implement this framework through a neural-network surrogate approximation that accelerates the repeated mapping from model parameters to nuclear and particle observables. Our fully-modular, neural-accelerated Bayesian framework interfaces the open-source MUSES Calculation Engine, the Bilby inference library, and the PyTorch machine-learning toolkit. We then apply the framework to the chiral mean-field model with a new generalized quartic vector self-interaction sector. We find that viable solutions are rare but broadly distributed within certain regions of parameter space, with the data constraining combinations of couplings more strongly than individual Lagrangian parameters. The resulting degeneracies imply that distinct saturation-compatible models can lead to qualitatively different descriptions of dense nuclear matter and, thus, of neutron stars, highlighting the need to combine terrestrial and astrophysical information.
Read the full abstract

All authors Isaac Legred, Mateus Reinke Pelicer, Veronica Dexheimer, Jacquelyn Noronha-Hostler, Nicolás Yunes

Quantum Physics

Quantum Motion from Local Transition Susceptibility

Jan Klaers

We characterize quantum motion through the susceptibility of a quantum state to weak localized state conversion. The susceptibility can be related to a passage speed characterizing local motion independently of probability transport. For individual WKB branches, it reproduces the magnitude of the local dispersion velocity in both propagating and evanescent regions. In the relativistic theory, the inferred passage speed is bounded by the speed of light, reaching this bound at the finite energy corresponding to the center of the mass gap, where the evanescent decay length equals the reduced Compton wavelength. This identifies the reduced Compton wavelength as the shortest stationary
Read the full abstract

Optics

Transient Depth Thermography for Probing Heat Transport

Dmitrii Shymkiv, Chun Wang, Yan Jiang et al. (+3 more)

Directly probing heat propagation inside materials remains challenging because conventional measurements are predominantly sensitive to surface temperature. Depth thermography has enabled non-contact reconstruction of subsurface temperature profiles from spectrally resolved thermal radiation under steady-state conditions. Here, we extend this approach into the time domain, establishing transient depth thermography to resolve the evolution of internal temperature during heat transport. By exploiting wavelength-dependent optical penetration depth, time-resolved thermal-radiation spectra provide access to temperature as a function of both depth and time. Tracking this spatiotemporal temperature field enables direct probing of heat propagation and quantitative determination of out-of-plane thermal conductivity and interfacial thermal resistance. We demonstrate the approach in fused silica, obtaining thermal conductivity within 2% of established values, and measure the temperature-dependent thermal conductivity of MgF2 over a broad temperature range where existing data are sparse and inconsistent. Numerical simulations further demonstrate its extension to multilayer thin films for probing interfacial thermal resistance. By extending depth-resolved thermal spectroscopy from steady-state to transient heat transport, this work establishes a new optical route for non-contact characterization of thermal dynamics in bulk and layered materials.
Read the full abstract

All authors Dmitrii Shymkiv, Chun Wang, Yan Jiang, Rajat Srivastava, Nandika D'Souza, Yuzhe Xiao

Chemical Physics

Aromatic Molecule Solvation in Liquid Water with Coupled Cluster Accuracy: The Balance of Pi-Interactions and Hydrophobicity

Nore Stolte, Harald Forbert, Yury Lysogorskiy et al. (+2 more)

Aromatic organic solutes in water exhibit a delicate balance between hydrophobic solvation and directional O-H$\cdots \pi$ hydrogen bonds, yet widely used force fields and state-of-the-art density functional approaches struggle to provide a consistent picture of these pivotal interactions. We introduce a data-efficient upfitting strategy to train a machine learning interatomic potential (MLIP) based on the graph atomic cluster expansion for aqueous aromatic molecules with CCSD(T) accuracy for condensed phase simulations, using only finite molecular clusters. We apply our method to aqueous toluene (C$_6$H$_5$CH$_3$). The resulting CCSD(T)-quality MLIP reproduces coupled cluster energies and forces in bulk and reveals that commonly employed methods do not capture the crucial balance between hydrophilic and hydrophobic solvation, distorting the interactions of aromatic molecules with their environment. Representative biomolecular force fields substantially understructure the hydrophobic solvation shell and misorient interfacial water, while overestimating $\pi$-contacts, yielding an inconsistent solvation balance. Even hybrid DFT and MP2 overestimate barriers to breaking of water-$\pi$ hydrogen bonds. Our workflow provides a practical, general route to CCSD(T)-quality condensed-phase simulations of aqueous solutions, and thus constructed interaction potentials now open the door to consistent, highly accurate benchmark studies of $\pi$-contacts and hydrophobic effects in biomolecular contexts such as solvation of proteins and DNA in aqueous environments.
Read the full abstract

All authors Nore Stolte, Harald Forbert, Yury Lysogorskiy, Ralf Drautz, Dominik Marx

Instrumentation and Methods for Astrophysics

MORFEO: Advancing Towards Final Design

Lorenzo Busoni, Guido Agapito, Marco Bonaglia et al. (+106 more)

The Multiconjugate adaptive Optics Relay For ELT Observations (MORFEO) is a first-generation adaptive optics module for the Extremely Large Telescope (ELT), designed to deliver a diffraction-limited, highly uniform 53x53 arcsec field of view to the MICADO near-infrared camera. As the project advances toward its Final Design Review (FDR), significant consolidations have been achieved across all subsystems. This paper presents an updated overview of the MORFEO system, highlighting its dual operational modes (MCAO and SCAO) and recent developments in its opto-mechanical architecture. We dedicate specific focus to the core adaptive hardware, detailing the fifth-generation post-focal deformable mirrors, the highly complex Laser Guide Star (LGS) objective zoom system required to track sodium layer variations, and the Natural Guide Star (NGS) low-order and reference sensing strategies. Furthermore, we detail the advanced pseudo-open-loop control strategy managed by a split Hard and Soft Real-Time Computer architecture. Finally, we report the latest end-to-end performance estimations obtained via the SPECULA simulation framework, demonstrating compliance with the stringent Strehl Ratio and sky coverage requirements under median atmospheric conditions.
Read the full abstract

All authors Lorenzo Busoni, Guido Agapito, Marco Bonaglia, Alfio Puglisi, Marco Xompero, Matteo Aliverti, Francesca Annibali, Carmelo Arcidiacono, Natalia Auricchio, Nicolò Azzaroli, Andrea Balestra, Alessandro Ballone, Louis Barbier, Andrea Baruffolo, Federico Battaini, Maria Bergomi, Andrea Bianco, Michele Cantiello, Giulio Capasso, Giulia Carlà, Enrico Cascone, Ed Chapin, Manal Chebbo, Simonetta Chinellato, Vincenzo Cianniello, Paolo Ciliegi, Mirko Colapietro, Jean-Jacques Correia, Giuseppe Cosentino, Elia Costa, Matteo D'ambrogio, Vincenzo De Caprio, Giuseppe De Luca, Nicholas Devaney, Ivan Di Antonio, Amico Di Cianno, Simone Di Filippo, Benedetta Di Francesco, Ugo Di Giammatteo, Chiara Di Prospero, Gianluca Di Rico, Andrea Di Rocco, Daphne Diretto, Christian Eredia, Simone Esposito, Jacopo Farinato, Italo Foppiani, Takashi Funakawa, Fulvio Gianotti, Laurence Gluck, Davide Greggio, Sylvain Guieu, Marco Gullieuszik, Yuuichi Harikane, Masahiro Ikoma, Laurent Jocou, Dan Kerley, Mikio Kurita, Salvatore Lampitelli, Tommaso Lapucci, Fulvio Laudisio, Yves Magnard, Demetrio Magrin, Hossein Mahmoodzadeh, Dheeraj Malik, Luca Marafatto, Laurence Michaud, Christophe Michel, Satoshi Miyazaki, Kentaro Motohara, David Mouillet, Thibaut Moulin, Matteo Munari, Kentaro Nagamine, Sylvain Oberti, Fabrice Pancher, Giorgio Pariani, Sophie Penger, Amedeo Petrella, Laurent Pinard, Cédric Plantet, Elisa Portaluri, Kalyan Radhakrishnan, Roberto Ragazzoni, Edoardo Redaelli, Edgar Renault, Colin Richardson, Marco Riva, Sylvain Rochat, Gabriele Rodeghiero, Luca Rosignoli, Bernardo Salasnich, Benoit Sassolas, Salvatore Savarese, Marcello Scalera, Pietro Schipani, Danilo Selvestrel, Mahshid Shiri, Mina Sibalic, Malcolm Smith, Sebastian Soler, Rosanna Sordo, Alessandro Tacchini, Alessio Taranto, Ludovico Teodori, Gabriele Umbriaco, Yoshinori Uzawa, Angelo Valentini, Jean-Pierre Véran

Earth and Planetary Astrophysics

Piercing through the Haze: Characterizing Titan-like terrestrial exoplanets with JWST

L. C. Mayorga, Jacob Lustig-Yaeger, Andrew P. Lincowski et al. (+5 more)

As we enter a new era of using JWST to characterize exoplanet atmospheres, a top priority is defining observational needs and parameters in the search for life on an exoplanet. Although some studies have begun to consider Titan-like exoplanet atmospheres, more work is needed to prepare for the potential discovery and characterization of Titan analogues with JWST and future missions. We explore the effectiveness of exoplanet atmospheric retrieval methodologies on the Cassini/VIMS-IR spectrum of Titan assuming agnostic haze properties and tholin hazes, as well as a self-consistent photochemical model. We compare our retrieved chemical abundances and haze profiles against fiducial values and Cassini/ISS-NAC UV observations and the forward modeled truths. We generalize these findings to a Titan-like exoplanet in the TRAPPIST-1 system and find that JWST-like observations have limited potential to identify features beyond methane in a Titan-like atmosphere, but may be able to identify the presence of the haze to a few hundred kilometers. The diagnostic features which would differentiate between different haze model (scattering) properties are shortward of 1\,\micron{} and further demonstrate the important role of nUV – optical observatories in constraining the properties of exoplanet atmospheres. We also find that agnostic priors for the bulk atmosphere can lead to a degeneracy in which a spectrally active gas ($\rm CH_4$) is erroneously favored as the dominant atmospheric constituent over a spectrally inactive molecule (N_2).
Read the full abstract

All authors L. C. Mayorga, Jacob Lustig-Yaeger, Andrew P. Lincowski, Kathleen E. Mandt, Ryan C. Felton, Adrienn Luspay-Kuti, Kristin S. Sotzen, Cameron A. Gutsgell

Quantum Physics

Let the Qudit Do the Jacobi: A Structured Quantum Algorithm for Spectral Decomposition

A. Mandilara

Jacobi diagonalization is a long-established numerical algorithm for the spectral decomposition of Hermitian and, more generally, normal matrices. In this work, we develop a qudit-native quantum realization of the Jacobi diagonalization algorithm for unknown unitary operators. The proposed framework avoids explicit reconstruction of the operator and controlled-unitary operations. Each elementary two-parameter Givens rotation is implemented through two sequential single-parameter quantum variational optimizations that are directly accessible experimentally. An interferometric protocol is further introduced for extracting the eigenvalues of the diagonalized unitary, up to an overall global phase. Numerical simulations on ensembles of Haar-random unitary matrices demonstrate that the proposed algorithm preserves the characteristic convergence behavior of the classical Jacobi method and exhibits the expected quadratic scaling in the number of elementary operations with the dimension $d$, comparable to its classical counterpart. The results establish the proposed algorithm as a structured quantum numerical linear algebra algorithm naturally suited to qudit architectures and provide a bridge between classical iterative matrix algorithms and their quantum realizations.
Read the full abstract

High Energy Astrophysical Phenomena

Time-resolved leptonic modeling of the prompt emission of GRB 211211A

Maria Petropoulou, Maria Gkoni, Konstantinos Xyloportas et al. (+3 more)

GRB 211211A is a long duration gamma-ray burst with a compact object merger origin. In this work, we model the time-resolved prompt-emission spectra of GRB 211211A within a leptonic radiation framework. Our goal is to infer the physical properties of the emitting region, study the temporal evolution of the radiating particle distribution, and make predictions for prompt emission at TeV energies. We perform Markov Chain Monte Carlo fitting of the time-resolved numerical spectral energy distribution (SED) models computed with the time-dependent non-thermal radiation code LeHaMoC. Our calculations include synchrotron emission and self-absorption, inverse Compton scattering including cooling in the Klein-Nishina regime, and photon-photon pair production. We find that the prompt emission of GRB 211211A between 10 keV and 10 MeV can be successfully reproduced by synchrotron radiation from a population of relativistic electrons. The spectral evolution during the first minute of the burst reflects different physical conditions in the emitting region. Our best-fit models favor fast-cooling solutions for the first 8 s, followed by a transition to slow-cooling solutions at later times. The accompanying synchrotron self-Compton emission extends to TeV energies, with predicted fluxes that would be detectable by CTAO for a burst similar to GRB 211211A, provided a sufficiently rapid response to a Fermi-GBM trigger or if the burst occurs within the CTAO field of view. The observed short variability of this burst requires very high Doppler factors ($\sim1000-2500$) throughout the burst evolution. Such extreme Doppler factors are difficult to reconcile with the jet Lorentz factor inferred from afterglow modeling unless the prompt-emitting regions are themselves moving relativistically with respect to the jet plasma.
Read the full abstract

All authors Maria Petropoulou, Maria Gkoni, Konstantinos Xyloportas, Stamatios I. Stathopoulos, Georgios Vasilopoulos, Apostolos Mastichiadis

Soft Condensed Matter

Modeling damage and fracture in additively manufactured polymeric triply periodic minimal surface lattices

Abhishek Gupta, Aditya Konale, Ke Ma et al. (+4 more)

Architected triply periodic minimal surface (TPMS) lattices offer superior specific energy absorption, toughness, fatigue strength, and tunability. While recent advancements have established rate-dependent viscoplastic constitutive models to capture the complex nonlinear deformation response of additively manufactured polymeric TPMS structures, predicting fracture and the resulting structural failure remains a significant challenge. We address this by performing systematic experiments on unit cells and lattices of various sizes under tension, compression, and non-monotonic loading. The experiments inform the development of a new constitutive model that captures the damage and fracture behavior of polymeric TPMS lattices. We first implement a high-fidelity viscoplastic deformation constitutive model from Ma et al. (2026) into finite element software Abaqus/Explicit via a user material subroutine. We then propose a damage initiation criterion for amorphous polymers based on stored elastic energy and equivalent plastic strain. The damage model is implemented in Abaqus using gradient-damage framework following Konale and Srivastava(2025). The damage model and numerical simulation capability are quantitatively and qualitatively validated using experimental results for a unit cell under non-monotonic loading and lattices under tension. The proposed damage model and simulation capability enable in silico design of architected polymer structures.
Read the full abstract

All authors Abhishek Gupta, Aditya Konale, Ke Ma, Keven Alkhoury, Pradeep Guduru, Yuri Bazilevs, Vikas Srivastava

Instrumentation and Methods for Astrophysics

What visibility-graph curvature measures in Forbush decreases: a calibration on the two largest events of solar cycle 25

D. Sierra-Porta

Discrete curvatures of visibility graphs are increasingly used as descriptors of geophysical time series, but their response to a transient has rarely been calibrated against the simplest properties of that transient. We carry out this calibration for the nodal Forman–Ricci curvature $\mathcal{F}$ of natural visibility graphs applied to neutron-monitor records of the Gannon storm (2024 May 10–11) and the 2025 June 1 Forbush decrease (FD), the two largest FDs of solar cycle 25, using 30-min NMDB data from six NM64 stations ($R_c \simeq 0$–$7$~GV), i.e.\ twelve station–event series. Curvature collapses at FD onset in every series (Cliff's $\delta = 0.63$–$1.0$), but a 6-h running standard deviation separates onset from quiet time more strongly (mean $\delta = 0.96$ vs $0.89$; mean block-permutation displacement $z = -27$ vs $-14$). Injecting synthetic decreases into the real pre-event records of each station shows that the curvature extreme follows $|\mathcal{F}_{\min}| \propto (A/\sigma)^{0.50}$ ($R^2 = 0.88$), where $A$ is the FD amplitude and $\sigma$ the station's quiet-time noise, and is independent of the duration of the main phase (exponent $0.006$ over 3–36~h). With $A$, $\sigma$ and the main-phase duration of each series as the only inputs, the calibration predicts the twelve observed extremes with standardized residuals of mean $-0.26$ and standard deviation $0.94$, and the observed extremes correlate with $A/\sigma$ at Spearman $\rho = 0.95$. Within the precision allowed by these data, nodal Forman–Ricci curvature of the whole-series visibility graph carries no information about these FDs beyond their amplitude relative to station noise; in particular, it does not distinguish the single-step Gannon decrease from the two-step June 2025 decrease.
Read the full abstract

Astrophysics of Galaxies

When X-ray Features Fail to Identify Intrinsic Emitters: Label Noise and Luminosity Overlap in Machine Learning Classification of AGN and Star-forming Galaxies

Jaymin Ding

Previously, we found that adding an X-ray flux feature to a Random Forest classifier of active galactic nuclei (AGN) and star-forming galaxies (SFGs) coincided with a decrease in classification accuracy from 97.51% to 89.26%, a counterintuitive result given the prevailing theory that X-rays are a reliable AGN diagnostic. We investigate this discrepancy through both astrophysical and machine learning lenses. On the astrophysical side, we show that the X-ray luminosities of AGN and SFGs in the sample substantially overlap across the canonical $10^{42}$ erg/s threshold, reflecting the moderate luminosity characteristic of an optically-selected sample and the contribution of high-mass X-ray binaries (HMXBs) to SFG emission. On the machine learning side, we argue that BPT-derived training labels carry instance-dependent label noise concentrated near the BPT demarcation line, where X-ray data would be most useful as a discriminator. We show that objects misclassified in 5-fold cross-validation cluster near the Kewley demarcation curve, with a median distance of 0.123 dex versus 0.743 dex for correctly classified objects (Kolmogorov-Smirnov $D = 0.745,\; p = 1.67\times 10^{-9}$). A controlled cross-validation decomposition shows that the previously reported decrease reflects predominantly sample selection: on a fixed sample, adding the X-ray feature leaves class-resolved metrics unchanged, and its permutation importance is consistent with zero across resampled splits. The classifier therefore makes negligible use of a physically informative feature, consistent with training labels coupled to the optical features. We conclude that future classifiers operating on optically-selected samples should employ independent label sources or noise-robust training methods.
Read the full abstract

Physics and Society

Conflict, mobility and fragmentation in the African interurban network

Andrew Renninger, Valentina Marin, Carmen Cabrera et al. (+1 more)

Roads make regional integration possible, but they also concentrate risk. When violence reaches a corridor that carries regional movement, the consequences can extend beyond the attacked place. We study this problem in Africa by combining interurban road data, georeferenced conflict events, and bilateral migration flows. Using a Hawkes-style self-exciting memory kernel, we estimate accumulated conflict intensity near roads from 2019 to 2022, and we route modelled movement between cities along the road network. As an empirical check on these modelled corridor flows, we show that country pairs connected by routes with higher accumulated conflict have lower bilateral migration. The association remains negative across alternative assumptions about spatial decay and is strongest for paths that cross regions, consistent with a corridor-deterrence channel rather than only displacement from violent places. We then use cascade and percolation simulations to examine how local disruptions propagate through the road network. Most simulated disruptions isolate relatively small populations, but 18.6% isolate more than one million people, and the largest isolates 13.3 million. Removing roads in order of conflict intensity reveals a tipping point, at which the giant connected component falls from 85% to 39% of the network. Our results identify the roads where violence most threatens regional integration and show how past conflict, mobility, and network structure combine to create persistent corridor vulnerability.
Read the full abstract

All authors Andrew Renninger, Valentina Marin, Carmen Cabrera, Rafael Prieto-Curiel

Mathematical Physics

Boundary Thermalization in Superdiffusive Energy Transport

Tomasz Komorowski and Stefano Olla

We study energy transport in a finite one-dimensional unpinned harmonic chain with stochastic nearest-neighbor momentum exchanges and Langevin heat baths at its endpoints. Such systems are known to exhibit superdiffusive transport driven by long-wavelength acoustic modes, leading to fractional macroscopic behavior. While fractional heat equations have been rigorously derived for infinite chains, the corresponding boundary conditions for finite systems in contact with heat baths remain unclear due to the nonlocality of the fractional Laplacian. Under the superdiffusive time scaling $t\sim n^{3/2}$, where $n$ is the system size, we prove that the averaged microscopic energy profile converges, as $n\to+\infty$, to a temperature field solving a fractional heat equation on $[0,1]$, with the generator given by a Neumann fractional Laplacian and additional nonlocal boundary terms induced by the heat baths. Our results provide a rigorous derivation of macroscopic boundary conditions for superdiffusive heat transport in open chains and introduce new boundary conditions for fractional Laplacians, that are motivated by a physical model.
Read the full abstract

High Energy Physics (Theory)

Some Remarks on the Spectral Geometry of the Gribov Horizon

Daniel G. Tedesco

We develop a local spectral framework for the Landau-gauge Gribov horizon that distinguishes gauge-orbit projection from degeneracy of the gauge-fixing Hessian. On a flat torus, spatially constant ghosts form a residual global-color kernel; after removal of this kernel, the reduced Faddeev-Popov operator is the normal Morse-Bott Hessian of the orbit-norm functional, whereas the covariant Laplacian defines the orthogonal connection. For the associated affine focal pencil, we prove a quadratic-form index theorem with a Morse-Bott endpoint. At a regular isolated crossing, the critical projector $P$ and invertible compressed derivative $\Gamma=P\dot{\mathcal{M}}P$ determine the spectral-flow jump and leading Laurent coefficient of the sourced ghost resolvent; for a simple zero, they also give the wall conormal. Crossings reached along affine rays from the positive region have negative-definite $\Gamma$, including symmetry-protected multiplets, while a second Schur reduction determines pole orders along tangential paths. A projected single-harmonic model checks the projected Feynman-Hellmann relation. For an $SU(2)$ hedgehog on $\mathbb R^3$, we construct a normalizable threshold state in every coupled spin-orbit channel and minimize over the full tower to obtain the exact stability interval $-2<g<1$. Dirichlet-box spectra approach these thresholds and serve as finite-volume comparisons; no numerical fit enters the continuum result.
Read the full abstract

Earth and Planetary Astrophysics

Growing Planets Produce Extreme Dust Signatures

Philip J. Carter and Zoë M. Leinhardt

Collisions between planetary bodies are essential to the assembly of rocky planets like the Earth, but they are extremely difficult to observe. We therefore rely on indirect signatures of planetary impacts such as extreme debris disks - bright infrared excesses around other stars. Extreme debris disks are thought to be the result of energetic collisions that ejected large amounts of vaporized rock which rapidly condensed into mm- or cm-sized dust. However, previously there has been no clear way to relate the observed mass of dust to the collision that produced it. Here, we show that the colliding bodies required are orders of magnitude more massive than the mass of dust observed. We find that more massive extreme debris disks require proportionally larger colliding bodies. As a consequence, the most massive observed extreme debris disks require collisions of Mars- to Earth-mass bodies. Extreme debris disks thus reveal the ongoing formation of rocky planets comparable in size to the rocky planets of our own solar system.
Read the full abstract

Quantum Physics

Comparing the three W-like states with the W state

Dafa Li

In [Phy. Rev. Lett., 98, 260501 (2007)] and previous papers, the W-like states were used in many quantum communication schemes, distillation, teleportation and superdense coding. So far, no one has compared the W-like states with the W state. We investigate the properties of three W-like states named as $|\vartheta ^{\prime }\rangle $, $|\eta ^{\prime }\rangle $ and $|\xi ^{\prime }\rangle $. We point out that $|\vartheta ^{\prime }\rangle $ (resp. $|\eta ^{\prime }\rangle $ and $|\xi ^{\prime }\rangle $) has the maximal von Neumann entanglement entropy (vNEE) $S(\rho _{A})=\ln 2$ (resp. $S(\rho _{B})=\ln 2$ and $S(\rho _{C})=\ln 2$) and the maximal tangle $\tau _{A(BC)}=1$ (resp. $\tau _{B(AC)}=1$ and $\tau _{C(AB)}=1$) while the W state does not. We also indicate that if some one of three qubits is traced out, then the remaining two qubits of $|\vartheta ^{\prime }\rangle $ (resp. $|\eta ^{\prime }\rangle $ and $|\xi ^{\prime }\rangle $) are more entangled than the two qubits of the W state by several entanglement measures. It means that the three W-like states have higher robustness against some particle loss than the W state. We show that $|\vartheta ^{\prime }\rangle $, $|\eta ^{\prime }\rangle $ and $|\xi ^{\prime }\rangle $ can be suitable for perfect teleportation and superdense coding but the W state cannot.
Read the full abstract

Quantum Physics

A Fibre-Integrated SPDC Heralded Single-Photon Source Using Zn-Indiffused PPLN Ridge Waveguides at Telecom Wavelengths

Peter Iveson, Paolo L. Mennea, Goronwy Tawy et al. (+7 more)

We report a fibre-integrated heralded single-photon source based on a commercial Zn-indiffused MgO:PPLN ridge waveguide operated in Type-0 degenerate spontaneous parametric down-conversion (SPDC). The device emits a broadband spectrum spanning approximately 70 nm across the telecom C-and L-bands, with an absolute brightness of $9.1\times 10^{9}$ pairs/(s mW). After accounting for optical losses, we determine an internal heralding efficiency of 58(5)%. The source maintains high purity, exhibiting a coincidences-to-accidentals ratio exceeding $9\times 10^{4}$ and a heralded second-order correlation of $g_{\text{h}}^{(2)}(0) = (5.53 \pm 0.46)\times 10^{-4}$. Low multi-photon noise and broadband emission demonstrate the viability of such platforms for wavelength-multiplexed quantum networking.
Read the full abstract

All authors Peter Iveson, Paolo L. Mennea, Goronwy Tawy, Rex H. S. Bannerman, Noe Palomar-Davidson, Lewis D. Wright, Patrick M. Ledingham, Peter G. R. Smith, James C. Gates, Corin B. E. Gawith