Papers

In the search for promising material candidates for hydrogen storage, we investigate from first principles derivatives of metal organic framework 5 (MOF-5), including isoelectronic substitution of the metal centers (Zn $\rightarrow$ Mg, Cd) and linker functionalization with NH$_2$, OH, and NO$_2$ groups. Metal-node substitution consistently stabilises and ligand functionalization systematically enhances H$_2$ binding at the metal-oxo cluster sites. The combination of Cd centers and NO$_2$ groups proves to be most efficient, yielding an adsorption energy of -15.58 kJ mol$^{\text{-1}}$, which substantially outperforms the storage ability of pristine MOF-5. Detailed electronic structure analysis clarifies how the local framework environment coordinates the guest molecule, providing a robust design framework to guide the experimental development of advanced adsorbent materials.

We investigate the collision dynamics of hydrodynamically interacting inertialess spherical particle pairs sedimenting in a homogeneous isotropic turbulent flow. The analysis focuses on the rapid-settling limit, in which the particle settling time across a Kolmogorov eddy is much shorter than the Kolmogorov time scale. We also consider continuum breakdown during lubrication interactions, which is important when the separation the particles is comparable to the $O(100)$ nm mean-free path of a gaseous media. Owing to the sub-Kolmogorov particle sizes considered here, we approximate the local flow field in the vicinity of a particle pair as a stochastic linear flow induced by the background turbulence. In the rapid-settling regime, the cumulative effect of turbulent strain fluctuations is weak, and the relative particle motion may therefore be described as a diffusive process. In addition, hydrodynamic interactions generate a net relative drift between the particle pairs. We obtain the hydrodynamic diffusivity and relative drift velocity from the Lagrangian autocorrelation function of the fluid velocity gradient evaluated along the settling trajectory. The rapid-settling assumption further enables us to relate the autocorrelation function to the turbulence energy spectrum. Using these results, we solve the advection-diffusion equation for the pair probability density function to determine the collision rate. We show that the ideal collision rate increases monotonically with increasing relative strength of gravity to turbulence, whereas the collision efficiency decreases monotonically over the same range.

Two-photon bound states in the continuum provide a stringent setting in which quantum interference must suppress radiative decay despite photon–photon interactions. Here, we prove a no-go theorem showing that a single nonlinear mode linearly coupled to a noninteracting bosonic continuum cannot support an interaction-active two-photon bound state in the continuum, provided the local spectral density vanishes only at isolated energies. Apart from this regularity condition, the result is independent of the continuum dispersion and the frequency-dependent coupling. Although such an exact bound state is forbidden, long-lived two-photon quasi-bound states remain possible. For a giant Kerr cavity nonlocally coupled to a waveguide, we derive the asymptotic scaling of the two-photon decay rate with the coupling-point separation from weak nonlinearity to the hard-core limit. We further identify a regime in which the two-photon resonance is substantially longer lived than the single-photon excitation. Our work establishes the limits of exact multiphoton confinement while opening a route to engineering long-lived interacting few-photon states.

We investigate how a surrounding dark-matter halo imprints itself on the QNM spectrum of a static, spherically symmetric black hole, considering two physically distinct density profiles: the Dehnen (1,4,5/2) and DC14 profiles. Both follow double-power-law forms, while the shape parameters of the DC14 profile are calibrated to galaxy-formation simulations and vary with the stellar-to-halo mass ratio $X=\log_{10}(M_*/M_{\rm halo})$, which controls the inner density structure of the halo. For both profiles, we compute the halo contribution to the metric function and the resulting effective potential governing axial gravitational ($s=2$) perturbations, and extract the fundamental QNM frequencies for the $\ell=2$ multipole. Our results show that the halo scale radius $r_s$ has the largest influence on the QNM spectrum among the halo parameters explored, reshaping the effective potential barrier near the light ring and shifting both the real and imaginary parts of the QNM frequencies. The density normalization, by contrast, plays a comparatively minor role for the Dehnen profile but is more consequential for DC14, reflecting the different inner structures associated with its varying $X$ values. The Prony-extracted frequencies show excellent agreement with the sixth-order WKB results, with relative differences remaining below $0.04\%$ across the parameter ranges considered. To our knowledge, this constitutes the first QNM analysis of a black hole embedded in a DC14 dark-matter halo. These results demonstrate the sensitivity of the QNM spectrum to the surrounding dark-matter environment and provide a consistent numerical framework for studying such environmental effects.

We establish spectral filtering as a control parameter for the conditional momentum and position correlations of SPDC biphotons used in quantum imaging. The conditional momentum uncertainty in spontaneous parametric down-conversion (SPDC) is strongly crystal-length and spectral-filter dependent along the walk-off axis; therefore, the effect is observed only in critically phase-matched (CPM) crystals such as $\beta$-barium borate (BBO) crystals, while quasi-phase-matched (QPM) crystals and the non-walk-off axis of BBO remain scaled strictly according to the standard pump waist size ($w_0$) dependent scaling law $1/w_0$-independent of the filter. In position space, the spectral-filter effect is universal and produces a flat-dip-rise (FDR) profile in every crystal class examined. Although this FDR profile was previously demonstrated in BBO only in the nondegenerate regime, our results establish its generality: the FDR dip is also present at exact degeneracy in QPM crystals, an unexpected feature that was previously thought to deliver a resolution advantage in the nondegenerate regime alone. Our treatment applies to all SPDC-based quantum-imaging regimes (including CPM and QPM crystals, walk-off and non-walk-off axes, degenerate and nondegenerate emission, and signal and idler filtering) and offers enhanced quantum-imaging resolution via the design rules presented-most prominently along the walk-off axis of CPM crystals (in far field) and across all transverse axes in the near field.

We investigate 7-branes in type 0B string theory, motivated by the recent proposal of Baykara, Dudas, and Vafa, which connects type 0B string theory with M-theory. On the $Q$-symmetric branch, the self-duality group of type 0B string theory is $\Gamma_0(2)$, whose Abelianization is $\mathbb{Z}\times\mathbb{Z}_4$. This implies the existence of two independent 7-brane charges. We construct explicit charge operators in terms of modular forms and identify the corresponding charged objects in gravity solutions. One is the ordinary D7-brane, while the other is a 7-brane carrying a nontrivial $\mathbb{Z}_4$ charge. We further construct a compact background consisting of eight such $\mathbb{Z}_4$ 7-branes using a restricted Weierstrass model. Remarkably, in this background the axio-dilaton is fixed to the constant value $\tau=(1+\mathsf{i})/2$, which coincides with the unstable de Sitter critical point proposed in the M-theory description of type 0B string theory. We also analyze fluctuations in the $Q$-odd sector and find that, although the corresponding equations of motion are globally well-defined in this background, the closed string tachyon remains unstable. Our results provide a concrete realization of new 7-branes in type 0B string theory and clarify their relation to its strong-coupling structure.

We study the exceptional line (EL) in the quasinormal modes (QNMs) of Reissner-Nordström-de Sitter black hole surrounded by a static thin shell of matter. For a conformally scalar perturbation, we derive the QNM condition by matching the interior and exterior solutions across the shell and show that higher overtones are particularly sensitive to variations of the shell and background parameters. A mode permutation between two QNMs reveals an exceptional point (EP). After extending the parameter space, this degeneracy forms a continuous EL. We show that the spectral response near the line is intrinsically directional. For a perturbation in parameter space $\epsilon\widehat{\mathbf u}$, the QNM splitting is $|\omega_+-\omega_-| =C_{\widehat{\mathbf u}}\sqrt{\epsilon}+o(\sqrt{\epsilon})$, with $C_{\widehat{\mathbf u}}=(\widehat{\mathbf u}^{T}\mathbf{K}\widehat{\mathbf u})^{1/4}$ and $\mathbf{K}$ is so-called spectral sensitivity anisotropy matrix. The tangent direction of EL is a null direction of $\mathbf{K}$, so that the leading square-root splitting vanishes along the exceptional line, whereas the two principal directions in the normal plane exhibit different sensitivities. Furthermore, the square-root branch structure makes conventional linear QNM parametrizations singular near an EL. We therefore construct an EL adapted parametrization which incorporates both the local geometry of the line and the nonanalytic QNM splitting.

Higher-form symmetries generalize conventional global symmetries and act on lower-dimensional submanifolds of a quantum system. While Abelian topological phases can be organized by 1-form symmetries that form a group, non-Abelian topological phases based on finite groups require 1-form symmetry operators governed by non-invertible fusion algebras. In this work, we make this statement precise in quantum double lattice models $\mathcal D(G)$ for finite non-Abelian groups $G$. We construct the electric, magnetic, and dyonic 1-form operators directly at the lattice fixed point and show that together they form a complete nonlocal diagnostic algebra for the topological Hilbert space. Using these operators, we explicitly determine the cylinder and torus ground-state subspaces for arbitrary finite $G$. Furthermore, we calculate the microscopic fusion and gluing of the 1-form symmetries and show that their topological deformation properties emerge after projection to the defect-free topological subspace. Our results establish ground states of non-Abelian quantum double models as a concrete microscopic realization of spontaneous non-invertible 1-form symmetry breaking and provide an operator language that may be useful for characterizing such states in quantum processors.

Spatially resolved EEDFs/IEDFs provide essential kinetic information about low-temperature plasmas (LTPs) and play a central role in determining transport, chemical reaction rates, and plasma surface interactions. While kinetic simulations directly resolve these distributions, experimental measurements remain challenging and are often invasive, spatially limited, or require assumptions regarding the distribution shape such as a Maxwellian. However, several macroscopic plasma observables can be measured non-invasively using advanced diagnostic techniques, providing spatially resolved information about the plasma state. An important inverse problem is therefore whether readily measurable macroscopic plasma quantities contain sufficient information to reconstruct the underlying kinetic state. In this work, we investigate this problem by learning a nonlinear mapping from spatially resolved macroscopic plasma observables to the corresponding spatially resolved EEDFs/IEDFs using a deep learning framework. Paired datasets comprising 2D macroscopic observables and spatially resolved EDFs are generated using 2D-3V PIC-MCC simulations. Three representative learning paradigms, a U-Net, a FNO, and a MeshGraphNet, are employed in this study to learn this inverse mapping. The predicted EDFs reproduce both bulk plasma and sheath characteristics with good agreement to the PIC-MCC reference data, with the FNO providing the best overall performance. Beyond conventional metrics, physics-based validation demonstrates that the reconstructed EDFs accurately recover the corresponding density and temperature, and rate coefficients. These results demonstrate that macroscopic plasma observables encode sufficient information to infer important kinetic properties in LTPs, providing a potential foundation for surrogate kinetic modeling and next-generation plasma diagnostics.

Timelike entanglement entropy (TEE) provides a Lorentzian boundary probe of bulk geometry, but its use for metric reconstruction depends on the holographic prescription and on the extremal-surface branch selected by that prescription. We study this inverse problem for strip-shaped TEE data and make these dependencies explicit. In the complex-valued weak extremal surface (CWES) prescription, the time-width dependence of TEE determines an Abel density $H(W)$ on a selected real branch; for Bañados-Teitelboim-Zanelli (BTZ) black holes this gives an analytic reconstruction of the blackening factor once the singularity endpoint fixes the radial origin. After developing a forward numerical method for the complex-coordinate prescription, we formulate it as the main reconstruction scheme for the asymptotically $AdS_{d+1}$ backgrounds with $d\geq 2$. On a chosen complex branch, the time-width dependence of TEE supplies the Abel input that determines the TEE-accessible density, while one additional geometric anchor is required to convert that density into a definite radial metric profile. With UV or horizon-scale anchoring and rational continuation from the reconstructed complex-path samples, the method reproduces the benchmark BTZ, four-dimensional Schwarzschild, and Reissner-Nordström (RN) blackening factors. However, the Gubser-Rocha example shows that a single strip observable with a nontrivial spatial warp factor determines only one functional combination of the metric functions.

We present MoMPy, an open-source Python package that provides a unified, declarative construction of moment matrices for semidefinite programming (SDP) hierarchies. The user declares operator labels together with a small set of structural relations, and MoMPy returns a matrix of SDP variable indices in which every implied identification has already been made, ready for CVXPY or any other modelling layer. Internally, the identification problem is recast as a word-rewriting problem on tuples of integers and solved with a memoised breadth-first closure coupled to a disjoint-set forest, so that each distinct monomial is processed exactly once per build, however many matrix entries it eventually labels. The central abstraction is independent of the physical scenario: the same construction handles tracial, state (NPA), and block-valued moments, with no notion of parties, settings or preparations. We demonstrate this generality on a tripartite Mermin inequality, the bipartite CHSH inequality, measurement compatibility in a steering scenario, state discrimination and dimension witnessing in prepare-and-measure scenarios, device-independent randomness certification, and certification of deterministic correlations from known ensembles. The construction is validated against an independent brute-force implementation and benchmarked across eight structurally distinct scenarios, spanning bipartite and tripartite Bell tests, heterogeneous-outcome, steering-type, jointly-measurable and network configurations.

Mechanical properties and dynamical mechanical analysis were performed on compact Spark Plasma Sinter samples. It has been observed that the sample with less porosity reflects the behavior of superelasticity response. Other samples show failure during first cycles that may be due to porosity. Compaction of metallic powder is one of the standard procedures in the field of powder metallurgy for the fabrication of bulk material. Consolidation of the sample as a function of sintering temperature plays a crucial role in the final compaction mechanism. However, the evolution of compaction, microstructure, phase transformation and mechanical properties as a function of sintering temperature is hardly disclosed. In this work, a correlation has been established between mechanical and microstructural properties of compact samples. The maximum compactness and the corresponding microstructure, porosity, texture, phase transformation, grain size, hardness, mechanical properties of compact samples were discussed. The research establishes mechanical properties-structure correlations for compaction of NiTi alloy in advanced engineering applications.

Detector-based first-arrival models and operator-based arrival-time observables provide two conceptually distinct approaches to the quantum time-of-arrival problem. Here we connect these approaches by using the positive unidirectional first-arrival current of Marchewka and Schuss (MS) as the basis for constructing a family of positive arrival-time operators and, after normalization, an arrival-time POVM. The first-arrival character is inherited from the dynamics with a Dirichlet boundary, while the detector response is introduced at the amplitude level through a non-negative spectral function $\lambda(k)$. For a one-dimensional free particle, resolution of the identity uniquely selects $\lambda(k)=\frac{\pi}{4k}$, yielding an arrival-time POVM. The normalized unidirectional current can therefore be interpreted as a generalized Born-rule probability density rather than as a hazard rate, as in the original MS formulation. We further show that the normalized one-sided MS amplitude coincides, up to an irrelevant phase, with the corresponding momentum-sector amplitude in Kijowski's arrival-time distribution. Consequently, the two directional contributions in Kijowski's distribution can be reproduced by two first-arrival problems defined on opposite sides of the boundary. This establishes an equivalence between the resulting arrival-time statistics while emphasizing the different physical interpretations: MS describes a first-arrival process with coherent momentum components, whereas Kijowski's POVM treats the two momentum sectors as separate directional contributions. Thus, the normalized unidirectional current provides a POVM description of first arrival at a point, combining detector-based dynamics with a positive-operator measurement structure.

A series of experimental results demonstrate a distinctive Raman response in plasmon-exciton coupled systems. The enhancement of Raman scattering varies for different phonon modes. We describe the microscopic dynamical process of this Raman scattering using quantum many-body theory. Unlike conventional Raman scattering involving electron-phonon interactions, the process in plasmon-exciton coupled systems is characterized by inelastic scattering between phonons and plasmon-exciton polaritons-formed through the coupling of plasmons and excitons-acting as intermediate states. We derive analytical expressions for the Raman intensity and enhancement factors for various phonon modes, which show excellent agreement with experimental data. Furthermore, experimental fittings indicate a substantial disparity in the linewidths of the upper and lower polariton branches, for which we provide a comprehensive theoretical explanation. Based on linear response theory, we propose a microscopic mechanism for the formation of plasmon-exciton polaritons, enabling the analytical calculation of their dispersions and linewidths. This approach naturally accounts for the significantly asymmetry observed in the linewidths of the upper and lower polariton branches. By characterizing the polariton-phonon scattering process at the quantum level, we reveal the fundamental physical mechanism driving polariton-enhanced Raman scattering. Our work establishes a universal framework for describing the dynamical evolution of coupled systems, providing a versatile paradigm for exploring the interactions between plasmons and other quasiparticles.

A system with two periodic directions carries two commuting holonomies \(a=(u,v)\in\R^2/\Z^2\). We determine their distinguished values while separating lattice, arithmetic, and observable effects. Maximizing the lowest twisted eigenvalue places \(a\) at a deep hole of the momentum lattice. For every rectangular torus the maximizer is antiperiodic, so complex multiplication is sufficient for torsion optima but not necessary. Let \(G_\tau^{-1}\) be the dual metric and \(D_\tau(a)\) the normalized zeta determinant of the twisted Laplacian. At the rotation-fixed deep holes of the square and hexagonal lattices, symmetry gives the exact determinant response \(-\operatorname{Hess}_a\log D_\tau=2\pi(\Im\tau)G_\tau^{-1}\). With spectral wavenumber \(\kappa=2\pi\), the lowest manifolds are fourfold and threefold, with gaps \(2\kappa^2\) and \(4\kappa^2/3\); phase errors split them linearly while their centroids remain stationary. We then give a finite-device realization: an \(8\times8\) microring lattice closed by two phase-controlled seams. At a reported coupling scale of \(16\) GHz, its exact square-lattice spectrum has a \(17.32\) GHz shell gap and a \(1.92\) GHz doublet separation for a \(0.1\) holonomy error; a triangular-link configuration gives a threefold qutrit manifold with an \(18.11\) GHz gap. This is a quantitative spectroscopy proposal, not a claim of topological protection or a completed device.

We report new quasilinear and fully-nonlinear 5th-order Schwarzian evolution equations. These are symmetry-integrable evolution equations in 1+1 dimensions, i.e. equations that admit Lie-Bäcklund symmetries, whereby it is required that the equations are kept invariant under the Möbius transformation for their dependent variable.

Quantum position-verification is a cryptographic task wherein a verifier attempts to establish the location in space of a prover. Recent experiments have implemented a well-studied class of position-verification schemes, known as the $f$-BB84 scenario, but their security under realistic loss and imperfect state preparation remains incompletely understood. We give a new lower bound on any attack on this scheme, in particular proving nearly-linear quantum gate lower bounds on the attacker, even when allowing the attacker to declare a transmission loss of up to $50\%$, allowing for the challenges prepared by the referee to be imperfect, and allowing the quantum messages used in the protocol to be arbitrarily slow. Our results are applicable to recent and upcoming experimental implementations of $f$-BB84, and in particular establish their security under a bounded quantum gate assumption on the attacker. The key ingredient is a tight analytic tradeoff for a lossy BB84 monogamy-of-entanglement game, valid without requiring the attackers' outputs to agree, which replaces observations previously made numerically.

In this paper we present a semi-analytical model for the velocity power spectrum in $\La$CDM cosmology for wave numbers $k<1/$Mpc. We mainly concentrate on the dominant divergence part but also present some results on the vorticity contribution. We divide cosmological parameters into evolution and shape parameters and model the dependence of the evolution parameter $h$ and of the shape parameter $\om_{\rm cdm}$ with an accuracy better than 2.5%. A surprising finding of our study is that the velocity power spectrum becomes independent of $\om_{\rm cdm}$ on nonlinear scales. A python implementation of the model is publicly available.

We construct $U(1)$-symmetric $SU(2)$ instantons on the Taub-NUT space with generic holonomy, and instanton number and magnetic charge $(k,m)=(2,0)$, $(1,1)$, and $(2,-1)$. We construct these instantons via the bow construction, a Nahm-like non-linear transformation which identifies them with a set of bow data solving an integrable ODE and a series of algebraic relations on an interval. We show how the bow data recovers the data for all corresponding $U(1)$-symmetric instantons on flat $\mathbb{R}^4$ and calorons on $\mathbb{R}^3\times S^1$ in various limits, and we demonstrate the existence of Taub-NUT instantons that do not limit to $\mathbb{R}^4$ instantons nor calorons.

The evolution of quantum field expectation values from an initial non-equilibrium quantum state can be followed numerically using the Truncated Wigner technique. It can track non-perturbative quantum phenomena, such as false vacuum decay, in real time with promising results. Nevertheless, it is an approximate method subject to quantum loop corrections. The extension of Truncated Wigner into a fully fledged effective field equation approach is discussed here, including corrections from higher loops and higher momenta.

Context. Galaxy groups and clusters are widely used to probe the evolution of the cosmic web and cosmology, while assuming that they are relaxed. Aims. We identify the properties of the brightest halo galaxies (BHGs) that can be used to predict the most likely sample of dynamically relaxed host halos. Our work combines thoroughly studied galaxy clusters with less frequently analysed groups. Methods. Our analysis was based on data from the IllustrisTNG simulations. We considered several observationally motivated parameters, including the offset of the BHG from the potential well of the host system ($d_\text{off}$) and from the r-band luminosity centre ($d_\text{lum}$), the distance between the brightest and second-brightest galaxies ($d_{12}$), and the r-band magnitude gap between them ($\Delta m_{12}$). The primary analysis was performed at redshift $z=0$, with an additional investigation of the redshift evolution of halo relaxation up to $z=1$. The observable proxies were applied to construct a halo mass function (HMF), which was then compared to the HMF of the relaxed sample defined from 3D information commonly used in theoretical approaches. Results. We find that $d_\text{off}$ and $\Delta m_{12}$ are effective indicators of group and cluster relaxation, particularly when used in combination. The selection criteria of $d_\text{off}<0.05~R_{200}$ and $\Delta m_{12}>1.6$ mag allowed us to reproduce an HMF that closely matches that of the relaxed halo population. These criteria can be applied to observations up to $z\sim0.2$ within a mass range $\text M_{200}\geq10^{12.5}\text M_\odot$ ($\text M_\text{*, BHG}\gtrsim10^{10.9}\text M_\odot$), including groups and clusters in the selection. In this mass range, $15-23\%$ of the systems are considered fully relaxed at $z=0$. The fraction of relaxed haloes decreases with redshift up to $z\sim0.4$, after which the decrease is far slower.

Imaging Earth-like exoplanets with coronagraphs on future large segmented space telescopes such as the Habitable Worlds Observatory requires contrasts down to $10^{-10}$ at separations below 100 mas, imposing segment phasing control down to a few picometers. We evaluate how this constraint can be relaxed by optimizing telescope and instrument design, quantifying the impact on performance stability under segment phasing aberrations. We propose a system-level approach, adjusting the primary mirror segmentation and the focal-plane mask size (inner working angle). We compare the passive robustness to segment phasing errors across systems, and the ability of a Zernike low-order wavefront sensor to reconstruct aberrations and recover target performance. Increasing the focal-plane mask radius or decreasing segment count improves both passive robustness and sensor reconstruction: Increasing the mask radius from 3.5 to 6.5{\lambda}/D relaxes phasing constraints by up to a factor 4 near the IWA, and reducing the segment count from 85 (5 rings) to 7 (1 ring) relaxes them by up to a factor 2; The same mask radius increase also doubles, on average, the sensor's sensitivity to photon noise across segment piston, tip, and tilt modes. To conclude, jointly optimizing the segmentation scheme and mask size, so the low-order PSD envelope is blocked by the mask, can significantly relax phasing requirements, complementing active correction, with direct implications for HWO.

It is well-established that at low baryon chemical potential, the transition from the confined hadronic phase to the deconfined partonic phase is a smooth crossover rather than a first or second-order phase transition. We develop a thermodynamically consistent hybrid equation of state to study the effect of global rotation on the equation of state across the QCD crossover that interpolates the hadronic and partonic phases. The temperature dependence of normalized thermodynamic observables, such as entropy density ($s/T^3$), pressure ($P/T^4$), energy density ($\varepsilon/T^4$), specific heat ($C_V/T^3$), and the square of speed of sound ($c_s^2$) in presence of rotation are investigated. The effect of non-zero chemical potential on thermodynamic quantities in presence of rotation is also studied. Our results show that increasing chemical potential enhances the thermodynamic quantities, whereas rotation suppresses them in the crossover region. Further, we investigate the effect of rotation on the conserved numbers susceptibilities and their correlations as a function of temperature. The susceptibilities and their correlations exhibit a systematic enhancement with increase in rotation in both the hadronic and partonic phases. These findings provide new insights into the interplay between rotation and QCD thermodynamics, which can have important implications for rapidly rotating strongly interacting matter produced in ultra-relativistic heavy-ion collisions.

The coordination properties of the emerging class of N-heterocyclic carbene-phosphinidene (NHCP) ligands have been reported to be strongly affected by the carbene (NHC) moiety, but a clear understanding remains strikingly limited. In this work the bonding features and reactivity of 13 NHCP gold hydride complexes, [NHCPAuH], bearing different classes of NHCs have been systematically explored and compared to carbene analogues, using a consistent computational protocol. The analyses reveal that, although the $\pi$-acceptor ability trend of NHCPs qualitatively parallels that of NHCs, the $\sigma$-donor ability trend reverses, with more $\sigma$-donating NHC moieties generating less $\sigma$-donating NHCP ligands. Concurrently, the nature of the NHC moiety impacts the coordination geometry at the P center, with the CNHC-P-Au bond angle appearing as a structural descriptor to monitor and/or design NHCP ligands with desired $\sigma$-donor properties. The NHCPs stronger $\sigma$-donor and weaker $\pi$-acceptor abilities compared to NHCs and their unique structural flexibility and electronic adaptability have been showcased to be directly controlled by the carbene moiety via modulation of the HOMO lone pair energy and its atomic phosphorous 3p character. The reactivity of [NHCPAuH] complexes with CO2, taken as a probe for potential NHCP applications in small molecule activation processes, demonstrates qualitatively similar mechanisms, with remarkably different activation barriers, which directly correlate with the NHCPs $\sigma$-donor ability, thus reflecting the high tunability of their bonding properties. This work provides insights and perspectives on the design principle of NHCP ligands, with a spotlight on the pivotal role of NHC moiety in modulating their electronic and steric properties, offering opportunities for burgeoning applications across diverse fields.

We report structural and physical investigations on the biaxial smectic-A phase exhibited by a compound consisting of asymmetric bent-core molecules. Upon cooling from the isotropic phase, the compound exhibits the following phase sequence: Isotropic (403.9 K) $\rightarrow$ biaxial Smectic-A (359.8 K) $\rightarrow$ Crystal. The polarized optical microscopy, X-ray diffraction, and polarization reversal current measurements clearly establish the biaxial nature of the smectic-A phase without any layer polarization. The measured layer spacing in the entire temperature range of the smectic-A phase is close to the molecular length. The schlieren texture in a homeotropically aligned sample shows both $\pm \frac{1}{2}$ and $\pm 1$ defects which indicate the biaxial nature of this smectic-A phase. The dielectric spectroscopy studies on the samples revealed Debye-type relaxation processes with the relaxation time following the Arrhenius equation with temperature. Interestingly, the observed biaxial smectic-A phase exhibits a remarkable electro-optic response for a planar-aligned sample without any reorganization of the smectic layer structure.

We report on the production of ultrahigh-charge relativistic electron beams and the development of a laser-wakefield acceleration platform at the LMJ facility. Making use of the kilojoule-class, sub-picosecond PETAL laser pulse focused onto a supersonic helium gas jet, electron beams carrying a total charge beyond 1 $\mu$C were generated, with energies up to $\sim$500 MeV. Given the ps-scale laser pulse duration, an on-target intensity approaching $10^{19}~\mathrm{W/cm^2}$, and a plasma density reaching 2% of the critical density, electron energisation arises from a combination of self-modulated laser wakefield acceleration (SMLWFA) and direct laser acceleration (DLA). The resulting electron spectrum exhibits a Maxwellian-like distribution, characteristic of this mixed SMLWFA/DLA regime. The total energy carried by the electron beam is estimated to be up to 17 J, within a sub-ps duration. A broadband Joule-level photon beam was also produced by Bremsstrahlung, demonstrating the potential for future applications. Experimental results are supported by start-to-end numerical simulations, including 3-D particle-in-cell and Monte-Carlo particle transport calculations. These findings pave the way for applications requiring high-charge electron beams, including the generation of high-power secondary radiation or particle sources. The use of these beams to probe matter in high-energy density states driven by the nanosecond-duration LMJ beams represents another promising avenue.

Stars of low and intermediate initial mass lose most of their stellar mass at the end of their lives during the asymptotic giant branch (AGB) phase. Determining their gas and dust mass-loss rates (MLRs) is crucial for quantifying the contribution of evolved stars to the life cycle of dust and gas in the Universe. The Atacama Large Millimeter/submillimeter Array was used to observe 38 carbon stars (C stars) in the large Magellanic cloud (LMC) and three C stars in the small Magellanic cloud (SMC) in the CO J= 2-1 line. Line profiles were fitted to derive stellar velocities and wind-expansion velocities (Vexp). CO emission is detected in two C stars in the SMC and 33 C stars in the LMC. This is the first detection of carbon monoxide around an AGB star in the SMC. One object in the LMC shows emission in $^{13}$CO. The wind-expansion velocity ranges from \sim7.5 to \sim30 km/s. Archival data were used to determine the pulsation periods as well as construct and model the spectral energy distributions using two dust radiative transfer codes. Mass-loss rates were independently derived from these two codes as well as from the intensity of the CO line, using a simple formula. On average, the dust-based MLRs higher than the MLRs based on the CO line by a factor of 1.6. Additional CO data in other transitions, combined with proper modelling, is required to further investigate this possible discrepancy. Mass-loss rates, pulsation periods, and expansion velocities were compared to a sample of Galactic C stars. There is a strong bias, as the Magellanic Cloud targets sample the highest MLRs and luminosities, yet they represent only a minority of stars in a Galactic sample. Comparing this sample with a similarly extreme set of Galactic stars with periods longer than 500 days, we identify no correlation between metallicity and either the MLR or Vexp.

We determine the exact strong converse exponent of quantum soft covering under the sandwiched Rényi divergence for all orders $\alpha\in[\frac{1}{2},\infty)$. For $\alpha\in[\frac{1}{2},1)$, the exponent is characterized by the two-parameter club-sandwiched mutual information, whereas for $\alpha\in[1,\infty)$, it is characterized by the order-$\alpha$ sandwiched Rényi mutual information. We also determine the exact strong converse exponent of privacy amplification against quantum side information under the sandwiched Rényi divergence for $\alpha\in(2,\infty)$, expressed in terms of the corresponding order-$\alpha$ sandwiched Rényi conditional entropy. To the best of our knowledge, these results provide the first exact characterization of the strong converse exponent of quantum soft covering and the first precise operational interpretation of the two-parameter club-sandwiched mutual information in the quantum setting. The key ingredient is that we establish the exponential rate of the $K$-functional, which is instrumental in deriving the strong converse exponent of quantum soft covering for $\alpha\in[\frac{1}{2},1)$.

We construct the natural generalization of stochastic quantization (in the Markovian sense) by considering jump-diffusion processes. This class of stochastic processes exhibits non-continuous paths, so-called Lévy flights. In the presence of jumps, action landscapes with barriers can be efficiently explored, improving and even restoring ergodicity where traditional diffusion approaches become inefficient. We explore different strategies for constructing efficient jump updates, which we deploy to address the benchmark problem of topological freezing in 2d U(1) gauge theory.

Metal halide perovskite nanoplatelets combine quantum confinement with structural anisotropy, yet how thickness and processing govern their internal crystal lattice versus collective organization remains unresolved. In this study, we separate internal structure, superlattice organization, and film texture using 2-5 monolayer CsPbBr3 nanoplatelets and larger nanocrystals across spin-coating and drop-casting routes. Grazing incidence X-ray diffraction analysis of the specimens indicates that orthorhombic-compatible signatures recur throughout the thickness and deposition series, with a preserved lattice-morphology relationship in which 020/040 and 101/202 lattice planes are associated with the platelet thickness and lateral dimensions, respectively. Upon deposition on the substrate, we notice a thickness-dependent crossover: 2-monolayer nanoplatelets remain predominantly face-on across deposition routes, whereas thicker nanoplatelets show marked processing sensitivity and orientational disorder. Processing therefore can be used as a tool to direct the NPL packing, establishing thickness as a key determinant of processing sensitivity.