Papers

We study the quantization of an M2 brane wrapping $\mathrm{AdS}_2\times S^1$ inside $\mathrm{AdS}_4\times S^7/\mathbb{Z}_k$, dual to the $\frac{1}{2}$-BPS circular Wilson loop in ABJM theory. The classical action and the one-loop contribution were previously shown to reproduce the gauge-theory localization result. Here we extend the analysis to the two-loop order. In an adapted static and $\kappa$-symmetry gauge the world-volume action contains no cubic interaction vertices, so that the two-loop correction is determined entirely by quartic interactions and is manifestly free of logarithmic UV divergences. We find that the bosonic and fermionic contributions combine into a perfect square $ {\mathscr X}^2$ where ${\mathscr X}$ is a linear combination of the bosonic and fermionic 3d Green's functions and their derivatives. The evaluation of $\mathscr X$ requires fixing the $\mathrm{AdS}_2$ boundary quantization of the massless fermionic modes. With the boundary conditions selected by the preserved supersymmetry, $\mathscr X$ vanishes and hence the complete two-loop correction is found to be zero. This result would not be consistent with identifying the M2-brane loop expansion directly with the large-$N$ expansion of the canonical, fixed-$(N,k)$ localization prediction. Instead, it agrees precisely with the recent proposal that the semiclassical M2-brane partition function should be matched to the gauge-theory grand-canonical ensemble, in which the Wilson loop expectation value is perturbatively one-loop exact. The vanishing of the two-loop correction thus provides a non-trivial test of this grand-canonical identification.

[Abridged] In this work, we compare neutron stars where dark energy or dark matter are present in the core, contrasting them against purely baryonic stars with the same central energy density. From this comparison, we find that the dark energy models are more constrained by neutron star observations than the dark matter models, suggesting that neutron stars can place strong constraints on dark energy parameters. We consider four configurations: purely baryonic neutron stars described by a piecewise polytropic (PP) equation of state (EoS), baryonic stars admixed with bosonic or fermionic asymmetric dark matter (ADM) cores, and stars with a dark energy core and baryonic shell, where the dark energy is described by the modified Chaplygin dark fluid (MCDF). Using the masses and radii of PSR J0740$+$6620, PSR J0437$-$4715, and PSR J0030$+$0451, we employ Bayesian inference to investigate how accounting for bosonic/fermionic ADM and MCDF cores affects the inferred neutron star properties. We find that MCDF cores, more than PP and ADM admixed models, substantially broaden neutron star mass-radius and pressure-energy density posterior distributions. Moreover, the MCDF EoS parameters can be tightly constrained. While bosonic and fermionic ADM cores decrease the inferred maximum mass, their posteriors strongly coincide with those of the PP model for ADM mass-fractions $F_\chi \leq 5\%$. These results demonstrate that current mass-radius observations cannot rule out MCDF cores, but they can constrain the MCDF parameter space to narrow regions. ADM admixed neutron stars, however, remain observationally identical to purely baryonic stars for all explored mass-fractions, even with improved mass-radius uncertainties. This suggests that mass-radius measurements alone are insufficient to detect ADM core inside neutron stars and that independent astrophysical or particle physics probes will be required.

Recent observations suggest intrinsic links between the stellar components of massive halos and their assembly histories. Using massive halos with $\log[M_{\rm halo}/M_\odot] \geq 13.0$ from the IllustrisTNG-300 simulation, we explore differences in secondary halo properties between samples selected by central galaxy stellar mass and satellite richness. For group-like masses, we find that halos selected by the outskirts stellar mass of their central galaxies between 50 and 100 kpc ($M_{\star,[50,100]}$) have similar halo mass distributions to those selected by intrinsic satellite richness ($\lambda_{10, R_{200}}$), but differ significantly in assembly history: $M_{\star,[50,100]}$-selected halos are more concentrated and formed earlier. At higher masses ($\sim10^{14}~M_\odot$), intrinsic richness becomes the better halo-mass proxy, but only when projection effects are ignored. We find that the difference-set test selects comparable halo-mass samples most effectively when the two proxies have similar scatter. Projection effects and baryonic physics do not alter the main trends but remain important caveats for observational applications. Our findings show that the central stellar mass-richness plane is a powerful tool for selecting halos with particular accretion histories, offering new insights into the galaxy-halo connection in the era of deep imaging and precision lensing surveys such as Euclid and LSST.

Recent work shows that the Schrödinger equation can be solved exactly based only on classical least action. The computation is based on first computing the multi-valued action solutions of the Hamilton-Jacobi equation, computing the classical propagated density along all stationary action multipaths, and finally constructing the exact kernel and wave function based on these classical multi-valued quantities alone. The method requires that the propagated classical square root density along each stationary action path is harmonic, as is the case for basic examples such as e.g., the double-slit, quantum tunneling, or the Einstein-Podolsky-Rosen experiment. For more complex cases, residual Bohm-like quantum potentials along each stationary action path can be eliminated through a time-rescaling. This paper proposes an extended version of the above construction which avoids the need for time-rescaling even in the most general cases. This is achieved by introducing in the Hamilton-Jacobi equation a real viscosity term, which classically simply corresponds to replacing a lumped parameter model with a continuum model including a volumetric stress tensor. This keeps the earlier construction unchanged, except that the real stationary action multipaths are now real stationary viscous action multipaths defined with respect to an associated modified Lagrangian. As in the earlier version, the construction extends straightforwardly to the special and general relativistic contexts, thus describing in a common language the quantum, classical, and relativistic cases. Note that the global Bohm potential term in the lumped Hamilton-Jacobi equation associated with a Madelung transform does not have a classical equivalent, while the volumetric stress tensor term in our viscous Hamilton-Jacobi equation directly represents the real paths of a classical deformed particle field.

Technological advances in neutral-atom platforms have opened a new path toward designing efficient protocols for fault-tolerant quantum computing (FTQC). However, each physical operation is still orders of magnitude slower than on other platforms, such as superconducting qubits. Therefore, architects must identify fast and efficient FTQC architectures, which require reliable modeling tools to explore various design choices across the software, classical hardware, and quantum device stacks of neutral-atom platforms. In this paper, we propose NAQsim, an open-source simulation framework for neutral-atom FTQC architectures based on transversal gates. As its key feature, NAQsim enables detailed full-stack architecture evaluation that opens opportunities to explore previously overlooked performance bottlenecks. As a first use case for NAQsim, we identify one such bottleneck, patch rotations, perform full-stack co-optimization, and finally derive a near-rotation-free architecture (D3-ROT). For practical FTQC benchmark workloads, D3-ROT achieves a 2.27x speedup from this single bottleneck alone, with minimal footprint overhead. These results point to a much broader space of full-stack optimizations that NAQsim makes accessible for transversal surface-code architectures and beyond.

The recently proposed concept of generalized superradiance (GS) allows for the generation of coherent radiation without the need for complex compression or prebunching of relativistic electrons. However, the quasiparticles in current GS schemes are formed through local electron accumulation and their sizes exceed 100 nm, restricting the achievable radiation wavelength. In this study, we demonstrate a realization of narrow quasiparticles with <10 nm widths through sheet-crossing. When an energy chirped electron beam collides with an intense laser pulse, lower energy electrons at the front slip back, forming an accelerating quasiparticle. These quasiparticles undergo transverse oscillations within the laser field, thereby extending GS emission from the Cherenkov regime into the synchrotron regime. Three-dimensional particle-in-cell simulations indicate the production of gigawatt-class chirped radiation in the 10-100 nm range. The proposed scheme is compatible with existing Thomson scattering facilities, paving the way for the generation of coherent ultrafast radiation.

Quantum confinement restructures the electronic phase space of ultrathin metals, but the resulting density-of-states (DOS) change is not generically large. We show that, within a three-dimensional confinement theory based on the suppression of long-wavelength electronic states, the Fermi-level DOS enhancement on the weak-confinement branch is bounded by $(4/3)^{1/3}-1\simeq10.1\%$. Instead, confinement-induced redistribution of electronic phase space can be strongly amplified by resonant denominators in the second-order susceptibility. A minimal double-resonance closure predicts giant amplification when the film thickness approaches $L_c=(2\pi/n)^{1/3}$, where $n$ is the carrier density, and a dominant optical pathway lies within a dephasing linewidth of resonance. Applied to recent Ag(111) measurements, the theory gives an effective phase-space carrier density parameter $n_{\rm eff}\simeq3.6\times10^{20}\,\mathrm{cm}^{-3}$, a tenfold enhancement of $|\chi^{(2)}|$, and hence the observed $\sim100$-fold increase of thickness-normalized second-harmonic-generation efficiency, together with the observed non-oscillatory thickness dependence.

For the first time, we proposed a novel stacking technology for DRAM scaling by flipping and backside processes, making full use of DRAM wafer's backside and investigating it on both 4F2 and 3D-DRAM. For 4F2 VCT, 2F2 Flip VCT featuring self-aligned back-to-back stacked 1T1C bitcell, with various BL and WL configurations, were studied and key process modules such as self-aligned stacked vertical channel, BL and WL formations, wafer bonding and flipping, substrate thinning and low-R Co storage node (SN) were successfully developed, addressing the potential thermal, misalign and parasitic concerns in the Flip VCT process. A full DRAM DTCO framework was also established from device to mat and chip level. Compared to 4F2 VCT DRAM with the same mat size, 2F2 FVCT delivers 27.5% less parasitics, 11% better sense margin, 16.3% higher charge sharing (CS) speed and 50% less area. For 3D-DRAM, a brand-new flip WL staircase design with peripheral circuit innovations was studied and proved to have 25% density gain, 15.1% faster turn-on speed and 6.8% less CS time, proving further extendibility of flip technology on DRAM.

Randomizing the readout time averages the mode interference in a quantum walk. We ask when this makes the site populations of a uniformly coupled $XY$ chain exactly uniform for every initial site. For $N\ge2$ spins, this is possible when $N+1$ is a power of two, a prime, or twice a prime. It is impossible when $15\mid(N+1)$, $21\mid(N+1)$, or $6\mid(N+1)$ with $N\ge11$. Uniformity uniquely fixes the averaged cosine coherences according to the mirror parities of the modes. Equal Bohr frequencies can impose incompatible coherence values. We classify these parity collisions using vanishing sums of roots of unity and prove existence in the positive cases through a phase distribution on a torus.

Whether the unusually strong nitrogen emission in nitrogen-loud (N-loud) quasars reflects high overall metallicity, enhanced nitrogen abundance relative to other elements, or both has long been debated. We analyze the broad-line region (BLR) abundances of 121 N-loud quasars at $2.13 \leq z \leq 3.90$ selected from the Dark Energy Spectroscopic Instrument Data Release 1 and construct a control sample of normal quasars matched in redshift, continuum luminosity, and virial black hole mass. Within the N-loud sample, metallicities inferred from N V/C IV span $\sim 3$-$50\,Z_\odot$ and are systematically higher than those inferred from the nitrogen-independent (Si IV+O IV])/C IV and Al III/C IV diagnostics, which agree closely and mainly span $\sim 1$-$20\,Z_\odot$. Compared with the matched controls, the N-loud quasars show systematically higher metallicities in both N V/C IV and (Si IV+O IV])/C IV, with median values approximately three times those of the controls. Notably, the discrepancy between the metallicities inferred from N V/C IV and (Si IV+O IV])/C IV becomes more pronounced toward the high-metallicity end of the N-loud sample, suggesting additional nitrogen enrichment beyond the overall metal enrichment. Together, these results indicate that N-loud quasars have both high overall BLR metallicity and enhanced relative nitrogen abundance, suggesting that relative nitrogen abundance is at least partially decoupled from overall metallicity. N-loud quasars therefore provide a high-metallicity laboratory for understanding how nuclear environments can produce unusual abundance patterns and offer a complementary view of how nitrogen enrichment arises across cosmic time.

We establish rogue wave patterns associated with the fourth Painlevé equation $(\mathrm{P}_{\mathrm{IV}})$ in the multi-component nonlinear Schrödinger and Hirota equations. The generalized Hermite and generalized Okamoto polynomials arise in representations of rational solutions of $\mathrm{P}_{\mathrm{IV}}$, and we show that their roots determine two classes of rogue wave patterns when one of the internal parameters of rogue wave solutions is large. Specifically, the generalized Hermite polynomials arise from rogue wave solutions represented by Schur-polynomial determinants with consecutive indices, whereas the generalized Okamoto polynomials arise from analogous determinants with index jumps of three. Numerical examples for both equations agree with the predictions.

Recently, continuous variables (CV) quantum computing, i. e. computing employing squeezed states, has attracted significant attention, as it enables to increase the dimensionality of the system. In CV protocols, homodyne detection plays a key role in the realization of the required gates and operations. Multimode squeezed light generated via parametric down-conversion (PDC) benefits from the broadband bandwidth, which encompasses multiple frequency modes. However, its broadband structure simultaneously requires the precise matching of the local oscillator (LO) with the squeezed light modes for their correct homodyne detection and processing. Achieving such matching is usually a challenging task, since the spectral bandwidth of the local oscillator is typically significantly narrower than the bandwidth of the squeezed-light modes. In this work, we propose and experimentally demonstrate a technique for expanding the bandwidth of the LO by passing it through the microstructured fiber. We validate the proposed concept by measuring squeezing in the modes of multimode squeezed light generated in type-0 and type-II PDC. We show that the broadened LO starts to spectrally match the modes generated via type-II PDC. The presented technique might be beneficial for implementing various CV systems and protocols.

We investigate solar-neutrino spin–flavor precession (SFP) induced by magnetic moments in the three-active-flavor framework. For Majorana neutrinos, SFP can convert solar neutrinos into antineutrinos of different active flavors. In the Dirac case, SFP instead produces sterile right-handed states and can lead to the disappearance of active neutrinos. Using the full $6\times6$ Hamiltonians and GS98 and AGSS09 solar profiles, we examine propagation-eigenvalue crossings at $B_\perp=0$ and the projected magnetic couplings between the corresponding states. For normal mass ordering and $1\leq E_\nu/\mathrm{MeV}\leq20$, we confirm the absence of finite-density Majorana crossings. A magnetically coupled Dirac crossing emerges above approximately $12~\mathrm{MeV}$ but involves only a subdominant electron-flavor component, limiting resonant disappearance. Nonresonant Majorana conversion nevertheless offers a distinctive lepton-number-violating solar $\bar\nu_e$ signal, motivating our sensitivity study for the Jinping Neutrino Experiment. For a proposed $3~\mathrm{kt}$ detector operating for five to ten years, we project a 90% C.L. sensitivity of $P(\nu_e\to\bar\nu_e)\simeq(0.85-1.3)\times10^{-5}$. In the $\mu_{12}$-only benchmark, optimistic solar-core transverse magnetic fields of $B_\perp=7-10~\mathrm{MG}$ imply a reach of $|\mu_{12}|\simeq(2.3-4.1)\times10^{-13}\,\mu_B$, numerically below existing direct-scattering limits and commonly quoted stellar-cooling bounds. This could enable Jinping to provide one of the most stringent projected terrestrial sensitivities to Majorana transition magnetic moments.

A first-principles investigation of heavy-light meson behaviour in hot QCD matter is essential for the interpretation of experimental results associated with open heavy flavour productions in relativistic heavy-ion collision experiments. Using anisotropic lattice ensembles from the FASTSUM collaboration with Nf=2+1 dynamical Wilson-clover fermions at non-zero temperatures, we study the B and B_s spectra at non-zero temperature. We use relativistic light quark propagators, while the b quark propagators are computed with a non-relativistic effective theory (NRQCD). We find that above T_c, thermal effects on the B meson states are more significant than those on the B_s states. Also, our results support the dissolution of the B-meson bound states above T_c.

A simple pedagogical discussion and visualization of certain Bell inequalities is presented with the help of a system involving two \textquotedblleft twins\textquotedblright, originally discussed in 2605.03104. These twins answer identically when the same `question' is posed, here exemplified with: Did you like breakfast/lunch/dinner? In analogy, for two entangled particles at distant locations, the `twin-like' quantum state is such that the same outcome for the same measurement (i.e. spin direction) is obtained. In the space $(X,Y,Z)$ of mixed moments (i.e. $X$ refers to breakfast-lunch correlation, being $1$ for same answers and $-1$ for opposite ones), the space of Bell local models is contained in a tetrahedron, while the quantum space is bound by an elliptope that embeds the tetrahedron. The whole no-signalling region in the $(X,Y,Z)$ space is the cube $[-1,1]^{3}.$ The twin scenario applies e.g. to the decay of the Higgs into fermions.

Ternary intermetallics use a ZrNiAl-type chemical structure known as a kagome system. Complexity observed in the phase diagrams of these compounds is attributed to the geometric frustration. The 5f-electron compound URhSn exhibits two phase transitions at 16 K and 54 K. No super-lattice reflections in neutron powder diffraction patterns are detected in the intermediate range of temperatures (16 K - 54 K). Recent resonant x-ray diffraction patterns for uranium ions in the intermediate phase suggest a chiral structure and a trigonal Sohncke space group. It is firmly established that a simple hexagonal space group describes the parent structure at room temperature. A ferroic order parameter that includes hexadecapoles is shown to characterize the trigonal Sohncke phase. Resonant x-ray diffraction by this phase is fully investigated with our symmetry informed theory. It repairs symmetry in the original data analysis by using a grey group, and it lifts an unjustified spatial condition on uranium positions. The theory uses axial atomic multipoles that satisfy sum-rules established in the first instance for x-ray dichroic signals. A confrontation between observed and calculated diffraction patterns lends support to a trigonal Sohncke phase, and exposes grounds for additional experimental work on an enigmatic compound.

Identical particles have dynamically invariant labels in all setups where their degrees of freedom can be partitioned into two parts, which we call internal and visible, with the visible part subject to unitary evolution, while the dynamically invariant internal part accounts for the partial distinguishability of particles. We give the explicit form of the visible state in terms of the indistinguishability function, generalizing the standard symmetrization/antisymmetrization postulate for bosons/fermions with internal modes. The indistinguishability function on the symmetric group accounts for the permutation symmetry of the dynamically invariant label state and gives a self-contained description of the symmetry spectrum of the visible state. It is shown that the indistinguishability of single particles emitted independently from a stable source is completely characterized by the projective measures on the symmetry spectrum. We reveal a hierarchy of successive upper bounds on the projective measure of indistinguishability in terms of marginal projective measures. We point out an experimentally feasible way to get the upper bounds on the indistinguishability of an arbitrarily large number of single photons by direct experimental readout of their marginal projective measures. We also analyze the indistinguishability of coherent superpositions and convex mixtures and resolve a recently posed problem.

Reporting the Fisher geometry of a trained variational quantum model is routine; quoting the shot budget that would establish it is not. Certifying an empirical Fisher matrix to relative Frobenius error $\varepsilon$ under coordinate-wise parameter shift costs $\Theta(B p^{2} V/(\varepsilon^{2} G))$ circuit executions, where $V$ is the measured readout variance and $G$ the measured squared gradient norm, with uniform allocation optimal in that class. One constant reproduces the cost of two circuit families whose exponents differ by a full power of $p$. The exponent is an identity in how $nV$ and $nG$ scale with the register, holding family by family to $0.001$ across 624 matrix-product-state cells once the finite-$p$ prefactor is removed. The cubic cost is therefore a finite-size window, set by whether the readout light cone grows with the register. A product family to 256 qubits gives $1.966$ (95% CI $1.934$–$1.997$); a brickwork entangler falls from $2.853$ below ten qubits to $1.715$ beyond sixty-four; a blocked entangler gives $1.984$ at a fixed cone width against $3.034$ at a proportional one. Fixed device connectivity fixes the cone, so a cubic budget from a small simulation overestimates a large machine, on top of hardware multipliers $2.07\times$ ($1.41$–$3.02$), $2.38\times$ and $1.91\times$ on ibm_marrakesh, ibm_fez and ibm_kingston. Cost-optimal readout weights cut the measured shot budget by $2.67\times$ ($1.33$–$4.00$) on hardware, flat from four to twelve qubits. A discrepancy model fitted on cheap circuits transfers its mean inside the calibration grid and, at six larger sizes named before the data, does not: nominal 90% intervals cover 36%, and split conformal is the only rung that stays near nominal.

In this paper, we study the decomposition, in the caterpillar or weak-coupling limit, of a spectral curve with two irregular poles of order two, namely a spectral curve of type $(2,2)$, into two spectral curves each having one regular singularity(order-$1$ pole) and one irregular pole of order two, namely spectral curves of type $(1,2)$ or $(2,1)$. Such spectral curves can be identified with a double Gelfand–Zeitlin (DGZ) system. We show that the Duistermaat–Heckman measure on the DGZ side can be identified with the Weyl measure on the gauge-theory side arises from gluing two quivers. Furthermore, the Fourier expansion of the isomonodromic tau function can be interpreted as a Peter–Weyl expansion in the real polarization of the DGZ system. On the other hand, we introduce the nodal caterpillar spectral network. Applying the caterpillar spectral network, we then obtain an explicit expression for the Stokes matrix up to a normalization factor. This expression agrees with the existing analytic formulas. Moreover, we identify the variation of endpoint normalization arising in the Stokes computation with the equivariant Euler class of the fluctuation complex over the Coulomb moduli space. Finally, using the gluing technique for spectral curves and the DGZ system, we conjecturally predict the perturbative coefficients of the higher-rank $P_{\mathrm{III}}$ isomonodromic tau function from the viewpoint of spectral geometry.

We investigate the evolution of the high-energy excess in Swift J1727.8-1613 during its 2023 flare state using joint Insight-HXMT and INTEGRAL/ISGRI observations covering 2-500 keV. Fits to the broadband spectra with a model including thermal Comptonization and disk reflection leave systematic positive residuals above ~150 keV. Adding a power-law component improves the fits and yields photon indices of 2.08-2.61, demonstrating that the high-energy excess beyond the thermal Comptonization continuum is present throughout the flare state. We also show that all spectra can be well described by the hybrid Comptonization model eqpair, without requiring any additional high-energy component. The fitting results indicate that the energy supply to the electrons transitions from predominantly thermal heating to non-thermal acceleration, and that the electron injection spectrum steepens abruptly near the onset of the flare state. During this evolution, the radio spectral index changes from approximately zero to negative values, accompanied by the ejection of three transient jet knots. Based on this temporal association, we discuss a possible connection between the increase in non-thermal power indicated by our spectral analysis and the ejection of the transient jet.

We study how the ground-state properties of the rho meson respond when the number of light-quark flavors N_f is driven towards the conformal window. The interaction is a symmetry-preserving, confining vector–vector contact interaction whose effective coupling carries a flavor dependence designed to encode the screening produced by fermion loops in the deep infrared. That interaction feeds the Schwinger–Dyson equation for the dressed-quark propagator and the homogeneous Bethe–Salpeter equation in the rainbow-ladder truncation, regularized in the Schwinger proper-time scheme so that quark production thresholds are absent while chiral symmetry remains broken. Raising N_f weakens the coupling, suppresses the dynamically generated mass and restores chiral symmetry together with deconfinement at a critical flavor number N^{c}_{f}. The vector channel responds differently from the pseudoscalar one. Because the $\rho$ is not a Goldstone boson, its mass is not protected by the symmetry that is being restored, and it simply follows the shrinking constituent scale, while the canonically normalized amplitude E_rho and the leptonic decay constant f_rho soften along the way. In this framework the rho sits above the nominal q\bar{q} threshold for every flavor number examined, so the state survives only as long as confinement removes that threshold. Dissociation is therefore governed by the divergence of the confinement length scale rather than by a crossing of the bound-state mass, and we contrast both criteria. The three elastic electromagnetic form factors G_E, G_M and G_Q, computed in the generalized impulse approximation, flatten as N_f grows, the zero crossing of G_E migrates towards the infrared and the charge radius expands, whereas the magnitude of the quadrupole moment decreases. The rho thus becomes a larger and rounder object as the theory approaches conformality.

Pressure is a critical thermodynamic parameter that profoundly influences the physical properties of glasses. Pressure-induced densification and structural transformation endow glasses manufactured under such conditions with exceptional mechanical and optical properties. Although pressure-treated glasses have been characterized by ensemble-averaged methods such as X-ray diffraction and Raman spectroscopy, their microscopic dynamics have rarely been addressed, limiting our understanding of the coupling among structure, dynamics, and mechanics. Here, using a binary hard-sphere colloidal glass confined in cylindrical capillary tubes, we impose a constant pressure on the particles through the tangential component of gravity. This approach enables the first investigation of pressure effects on colloidal glasses. We find that the dynamics are substantially frozen, whereas the structural change remains comparatively mild. At low pressure, spatial correlations among structural, dynamical, and local elastic heterogeneities are observed. Remarkably, dynamical anisotropy emerges in response to pressure, characterized by faster motion parallel to the pressure direction than perpendicular to it. This anisotropy is attributed to an instability induced by the strong pressure force. Concurrently, structural and dynamical heterogeneities are strongly suppressed under pressure. Our experiments characterize the microscopic dynamics of colloidal glasses under pressure and offer design principles for the manufacturing protocol of glass materials.

The high-energy end of the gamma-ray burst (GRB) prompt spectrum carries information on the physical conditions of the relativistic outflow, but the number of well-characterized spectral cutoffs is small. We present a systematic search for high-energy spectral cutoffs in the time-integrated prompt spectra of 139 GRBs observed by Fermi between 2008 July and 2025 December, selected to have broadband coverage either through a LAT detection or through bright BGO emission. Joint GBM, LLE, and LAT spectra over $T_{90}$ are fitted with four empirical models and compared using the Bayesian information criterion, yielding 106 bursts with well-constrained cutoff energies $E_c$. An empirical two-component Gaussian mixture model applied to $\log_{10}(E_c/\mathrm{MeV})$ separates a low-$E_c$ group from the main distribution at $E_c=2.12$ MeV; the 77 bursts lying firmly above this boundary are interpreted within the internal $\gamma\gamma$ pair-opacity framework. Combining $E_c$ with wavelet-based minimum variability timescales (median $0.119$ s), we infer bulk Lorentz factors of $11.7$ to $2.78\times10^{3}$ (median 145) and emission radii of $\sim10^{13}$ to $10^{15}\,\mathrm{cm}$. Neither the $\Gamma$-$L_{\mathrm{iso}}$ nor the $\Gamma$-$E_{\mathrm{iso}}$ relation is statistically significant for the full sample, whereas the 27 bursts with measured redshifts show a moderate $\Gamma$-$L_{\mathrm{iso}}$ correlation with a slope of $0.36_{-0.23}^{+0.22}$. We further find a strong rest-frame correlation between the cutoff and peak energies, $E_{c,z}\propto E_{p,z}^{2.15_{-0.97}^{+0.96}}$, for the 26 bursts with measured redshifts, which persists after controlling for redshift.

This paper investigates Anderson localization in subwavelength elastic periodic systems with random perturbations. For the unperturbed system, we use layer potential techniques to reformulate the eigenvalue problem as boundary integral equations, and derive asymptotic formulas for the subwavelength eigenvalues. For perturbed systems, we apply the Floquet transform to obtain a periodic formulation and derive equations determining the resonant frequencies under general perturbations. Numerical experiments for perturbed periodic monomers and dimers agree with the theoretical predictions. We further demonstrate Anderson localization by increasing the strength and number of random perturbations. These results provide a mathematical foundation for understanding subwavelength localization in elastic metamaterials.

Slowly sheared granular materials generally store mechanical energy and dilate between abrupt failures that release energy and compact the material. Here, simultaneous measurements of torque, layer thickness, acoustic emission, and photoelastic force networks reveal all four combinations of energy release or storage with contraction or dilation in a compressed granular fault. Most strikingly, some avalanches both dilate the layer and increase the elastic energy transmitted to the resisting boundary. These events reorganize force chains beyond the shear band and produce a distinct acoustic response. The results show that an avalanche need not relax a driven disordered material; it can instead redistribute stress into a more highly loaded configuration, a mechanism with potential relevance to the physics of both laboratory and natural faults.

Passive photonic structures offer a potential route toward reservoir computing by exploiting intrinsic optical propagation, delay, interference, and memory effects for temporal information processing. This work investigates whether a chirped Bragg grating (CBG) can exhibit fundamental physical properties relevant to a passive photonic reservoir. Rather than presenting the CBG as a complete reservoir computer, the study provides an early proof-of-concept assessment based on experimentally measured device characteristics. Wavelength-dependent group delay and reflection coefficient measurements obtained from a silicon photonic CBG are incorporated into a distributed delay model in which multiple delayed contributions form the reservoir states. The resulting system is examined with respect to distributed delay, fading memory, temporal mixing, and memory capacity using a linear readout based on the standard memory capacity formulation. The results demonstrate that the measured CBG response provides a distributed temporal memory over the experimentally observed delay range and produces temporal mixing through the superposition of multiple delayed contributions. The memory capacity analysis further indicates that past input symbols can be reconstructed from the distributed delay states, providing quantitative evidence of temporal information retention in the measured CBG response. These results suggest that a passive CBG possesses several physical characteristics relevant to reservoir computing and may therefore provide a simple photonic substrate for reservoir-like temporal processing. The study is intended as an initial proof-of-concept, providing a foundation for future experimental and task specific investigations of passive CBG-based photonic reservoirs.

Many engineering building blocks behave as multi-port linear time-invariant systems. RF cavities, photonic devices, and superconducting quantum chips, despite their different underlying physics, all share a common mathematical structure for their port-level response. Each entry of the response matrix is a sum of contributions from a small number of intrinsic resonant modes, the pole-residue form. A model capable of predicting such responses for arbitrary geometries and arbitrary port configurations, while simultaneously extracting the underlying eigenmode structure, would therefore establish a foundational design principle spanning all these domains. We propose a neural framework that learns this modal decomposition end-to-end, supervised only by system-level observables and without supervising the modal parameters themselves. The architecture decomposes into a port-independent pole predictor and two port-dependent coupling predictors whose outputs are combined entry-wise, separating intrinsic from port-dependent features. This factorization yields a single trained model that generalizes to port counts unseen during training, dissolving the $\mathcal{O}(N^2)$ scaling barrier of direct regression. Despite no modal supervision, the freely-parameterized poles converge to physically meaningful eigenmodes, verified by cross-validation against the AAA rational approximation algorithm. We instantiate the framework in radio-frequency electromagnetic surrogate modeling. A model trained only on 2-port data accurately predicts $N$-port responses unseen during training.

Entanglement harvesting provides an operational means of probing the nonlocal correlation structure of quantum fields through localized detector-field interactions. Although harvesting has been investigated in a wide variety of spacetime backgrounds and quantum field states, existing studies largely focus on individual detector configurations or specific physical settings. In this work, we develop a unified perturbative framework for entanglement harvesting with localized Unruh-DeWitt detectors that is applicable to arbitrary detector trajectories and quantum field states through the corresponding Wightman function. By expressing the detector response in terms of dimensionless variables and analytically reducing the perturbative integrals to numerically efficient representations, the framework enables a systematic exploration of multidimensional harvesting landscapes, phase boundaries, and harvesting robustness. As representative applications, we investigate inertial detectors in the Minkowski vacuum, thermal field states, and uniformly accelerated observers. We show that finite temperature enhances both the local detector response and the nonlocal exchange amplitude, leading, within the perturbative Gaussian-switching framework considered here, to an enlargement of the harvesting region in parameter space. The resulting harvesting landscapes provide a global characterization of detector-field interactions and demonstrate how temperature and observer motion reshape the competition between local detector noise and nonlocal field correlations. The framework developed here provides a unified and readily extensible methodology for investigating entanglement harvesting across a broad class of relativistic quantum systems.

Thin-film silicon solar cells exhibit weak absorption at longer wavelengths of visible light due to their limited optical thickness. To overcome this inherent limitation, a hybrid nanocone-nanohole light-management architecture is proposed by integrating front-surface silicon nanocones with embedded air-filled nanoholes in the absorber layer. The nanocones provide a gradual refractive-index transition that suppresses front-surface reflection, while the nanoholes enhance optical confinement through multiple scattering and internal reflection. The structural parameters are systematically optimized using finite-difference time-domain (FDTD) simulations coupled with electrical device modeling. Under optimized doping conditions and isothermal steady-state operation, the optimized design yields a short-circuit current density of 34.64 mA cm-2, an open-circuit voltage of 0.82 V, a fill factor of 86.27%, and a power conversion efficiency of 24.42%, representing a 17.74% improvement over a comparable nanohole-based design. Furthermore, coupled opto-electro-thermal simulations show that the proposed hybrid nanocone-nanohole structure retains 95.21% of its efficiency under non-isothermal operation up to45 degree celsius, demonstrating excellent thermal stability. These results highlight the potential of the proposed hybrid nanocone-nanohole design as an effective light-management strategy for high-efficiency and thermally robust thin-film silicon solar cells.

Directional dissipation can concentrate relaxation modes in space, but connecting this accumulation to controlled microscopic processes in correlated matter requires separating virtual charge motion from spin coherence. We study this connection in a half-filled Hubbard chain with reciprocal hopping and number-conserving, direction-selective returns of virtual doublon–hole defects. Eliminating charge defects and then Mott coherences yields asymmetric spin-exchange rates under an explicit separation of timescales, with full short-chain dynamics supporting the reduction on finite exchange times. Balanced random returns concentrate the stationary population and several low-lying right modes at sample-selected positions rather than a predetermined edge, producing random Liouvillian skin localization despite zero end-to-end logarithmic rate bias. The accumulated rate imbalance determines an exact finite-density hard-core stationary state and a one-particle activated relaxation scale governed by random barriers. This connection between locally calibrated return rates, many-body stationary weights and slow relaxation offers a means of controlling transport in constrained open quantum matter without changing the reciprocal Hamiltonian.