Search Results (1,376)

Landau–Zener–Stückelberg–Majorana (LZSM) interference describes the coherent superposition of nonadiabatic transitions when a quantum system is driven through an avoided crossing, but its classical optical analog remains largely unexplored. This work establishes an optical-resonator-based platform for exploring LZSM interference in atomic polarization dynamics using temporal coupled-mode theory. By exploiting the formal correspondence between the cavity mode and atomic polarization in a weakly driven two-level system (TLS), exact analytical solutions are derived for linear frequency sweeps and sinusoidal modulation. The results reveal that the Landau–Zener transition of atomic polarization occurs even when the input frequency transiently sweeps across resonance. The finite temporal memory inherent in the cavity response gives rise to Stückelberg interference, manifesting as oscillations in transmission and cavity energy. The dependence of the interference pattern on sweep rate, linewidth, and modulation is systematically analyzed, and a non-monotonic behavior of oscillation amplitude versus the cavity linewidth is identified. Furthermore, the conventional critical coupling concept is reexamined in the nonadiabatic regime, where counterintuitively the deepest transmission dip occurs under over-coupling rather than critical coupling. Finally, an inverse-design approach engineering both the amplitude and frequency of the input frequency is introduced to tailor the LZSM interference pattern. Our results provide a new platform to all-optical simulation of complex quantum interference. Full article

We develop a framework in which quantum field equations are reconstructed from a multi-branch Hamilton–Jacobi structure supplemented by density functionals on configuration space. Each branch is defined by a solution of a functional Hamilton–Jacobi equation, while the associated density encodes measure-theoretic and dynamical information. Under suitable analytical assumptions, we show that the superposition of these branchwise contributions yields a wave functional satisfying the functional Schrödinger equation. The construction is established in a mathematically controlled setting, including finite-dimensional regularizations and a continuum limit under appropriate convergence hypotheses. Explicit examples demonstrate the exact reconstruction of both free and interacting scalar quantum field equations. Extensions to fermionic and gauge fields are outlined, highlighting the role of graded structures and constraints. Beyond the reconstruction result, the framework provides a structural reinterpretation of quantum theory. Classical dynamics is encoded in the space of Hamilton–Jacobi solutions, while quantum phenomena arise from the coherent superposition of these classical configurations through density and phase. From a geometric viewpoint, the construction is naturally related to multisymplectic structures and admits a cohomological interpretation. This approach establishes a direct bridge between classical variational principles and quantum field theory, offering a unified perspective on the emergence of quantum behavior from structured ensembles of classical configurations. Full article

The quantum–classical transition is one of the most frequently invoked concepts in modern physics. Yet the notion of classicality itself is far from unique. Depending on the physical context, classical behavior may be associated with decoherence, the semiclassical limit, thermodynamic averaging, suppression of correlations, emergence of collective order, or geometric simplification of statistical state space. These viewpoints are often presented as if they described a single phenomenon, although they emphasize different physical mechanisms and different operational criteria. In this article, we examine the principal notions of classicality that appear across quantum theory, statistical physics, condensed matter physics, and information geometry. We compare the corresponding mechanisms of classical emergence and analyze the physical quantities commonly used to characterize them, including coherence, entanglement, fluctuations, correlation length, Fisher information, statistical complexity, and information-geometric curvature. We argue that many apparently distinct routes toward classical behavior share a common structural feature: a reduction of effective fluctuation freedom (REFF). From this perspective, classicality may be interpreted as an emergent regime in which the accessible fluctuation manifold becomes progressively constrained, stabilized, or geometrically simplified. This viewpoint naturally unifies decoherence, semiclassical localization, thermodynamic averaging, decorrelation, and collective organization within a common conceptual framework. Rather than representing a unique physical process, the quantum–classical transition appears as a family of related mechanisms through which complex quantum fluctuation structure gives rise to effective macroscopic classical behavior. Full article

Nanostructured copper oxide (CuO) holds significant promise for optoelectronic, photocatalytic, and biomedical applications, yet its performance is critically dictated by its morphology, crystallite size, and surface chemistry. In this work, pure monoclinic CuO nanoparticles were successfully synthesized via a facile, kinetically controlled aqueous co-precipitation route using three distinct precursor salts: copper acetate (CO-Ac), copper sulfate (CO-S), and copper chloride (CO-Cl). To achieve precise architectural control, the synthesis was conducted near the thermodynamic solubility limit of the precursors combined with an abrupt NaOH injection, effectively decoupling the nucleation stage from crystal growth. Rietveld refinement of X-ray diffraction (XRD) data confirmed the structural integrity of the monoclinic lattice across all samples, χ² = 1.04 − 2.02, crystallinity 53–55%, while demonstrating that the precursor anion strongly governs the volume-averaged crystallite size, which expanded from 16 nm (CO-Ac) to 30 nm (CO-S) and 52 nm (CO-Cl). Morphological analyses revealed that acetate acts as a non-specific capping ligand, promoting isotropic, quasi-spherical nanoparticles that aggregate into high-surface-area (69.04 m²/g) “bead-chain” assemblies. Conversely, sulfate and chloride ions act as shape-directing agents via facet-selective adsorption on nucleation seeds, yielding two-dimensional plates and anisotropic acicular/needle-like architectures, respectively. X-ray photoelectron spectroscopy (XPS) and modified Auger parameter (α ~1851 eV) analyses confirmed the absolute dominance of Cu²⁺ states, with a minor fraction (~2.5 mol %) of lower-coordinated surface edge states. XPS further unveiled that the strongly alkaline environment (pH ~14) drives precursor-dependent surface chemistry: CO-Ac nanoparticles retain a clean, hydroxylated layer with minor acetate residues, whereas CO-S and CO-Cl samples develop a passive copper hydroxycarbonate (Cu₂(OH)₂CO₃) surface barrier that blocks active sites and reduces porosity. Optical properties analyzed via UV-vis diffuse reflectance revealed a pronounced, size-dependent blueshift relative to bulk CuO, with fundamental indirectly allowed bandgaps of 2.6 eV, 2.36 eV and 1.93 eV for CO-Ac, CO-S and CO-Cl samples, while the direct bandgaps shifted from 3.0 eV, 3.2 eV, and 3.57 eV for the mentioned samples. This behavior is attributed to quantum confinement governed by fine individual nanocrystals. These findings establish that precursor engineering offers a robust pathway to tailor the morphological, optical, and interfacial properties of CuO nanostructures for targeted functional devices. Full article

Zentropy theory has emerged as a multiscale thermodynamic framework that bridges quantum mechanics, statistical mechanics, and macroscopic materials behavior by embedding internal degrees of freedom within configurational ensembles. This review summarizes its theoretical foundations, representative applications, current limitations, and future directions. By incorporating intrinsic configurational entropy and free-energy-based statistical weighting, zentropy theory enables improved descriptions of phase stability, thermal expansion, and phase transitions in materials such as ferroelectrics, magnetic systems, high-entropy materials, and superconductors. Recent extensions also connect zentropy with artificial intelligence through data-driven thermodynamic modeling. Despite these advances, several challenges remain, including the ambiguity of configurational coarse-graining, strong cross-degree-of-freedom coupling, propagation of density functional theory errors, and limited applicability to delocalized or non-crystalline states. Future progress will require theoretical advances, including non-ergodic extensions, rigorous mathematical treatment of recursive multiscale entropy, and improved descriptions of low-temperature quantum effects. These efforts should be complemented by standardized software workflows, machine learning integration, and robust uncertainty quantification. Addressing these bottlenecks will help to further develop zentropy theory as a critically assessed framework for multiscale thermodynamic modeling and materials design. Full article

The transition from post-quantum cryptographic standardization to operational deployment requires more than the selection of a quantum-resistant algorithm. It requires traceability from the mathematical assumptions of the primitive to implementation requirements, protocol composition, migration controls, and runtime governance. This paper develops a cross-layer assurance framework for deploying the NIST-standardized Module-Lattice-Based Key-Encapsulation Mechanism (ML-KEM) within crypto-agile Zero Trust architectures. The paper presents a simplified algebraic model of the public-key encryption operations underlying ML-KEM, emphasizing quotient-ring arithmetic, module operations, controlled noise, and cancellation of the principal bilinear term. It then distinguishes this explanatory model from the complete mechanism specified in FIPS 203, including standardized sampling, encoding, compression, hashing, key derivation, ciphertext consistency checking through re-encryption and comparison, implicit rejection, and prescribed decapsulation behavior. The principal contribution is an assurance framework connecting three levels: algebraic assurance, implementation assurance, and cryptographic governance. A deployment architecture, threat model, crypto-agility lifecycle, and bounded AI-assisted monitoring model are presented to show how ML-KEM profiles can be inventoried, approved, negotiated, observed, migrated, rolled back, and audited without altering the underlying cryptographic guarantees. The resulting framework provides a technically grounded bridge between ML-KEM mathematics and practical post-quantum migration in Zero Trust systems. Full article

Quantum relativistic solutions of a “square-root” version of the Klein–Gordon equation, for a particle in a one-dimensional Morse potential, are presented using methods previously proposed and applied to a particle in a harmonic oscillator. The methods lead to both numerical and analytical solutions, with the latter allowing smooth variation of the system parameters from non-relativistic to ultra-relativistic limits. Analytical expressions for the energy levels and wavefunctions are obtained, as solutions to a Schrödinger-type equation, including relativistic effects through a state-dependent rescaled mass. The eigenstates of the Morse potential exhibit suitable and smooth behavior and approach the corresponding harmonic oscillator solutions as the depth of the Morse potential well increases, as expected. A comparison is also presented between the relativistic harmonic oscillator obtained with this method and the so-called “Klein–Gordon oscillator”. Full article

Quantum circuit simulation is usually evaluated through final numerical accuracy, while the dynamics of stochastic execution itself are less explicitly characterized. This work presents a precision-elastic persistent stochastic execution framework based on integral stochastic computing (ISC), where execution behavior is controlled by stream length N and ISC multiplicity m, where m represents the number of aggregated stochastic sub-streams per cycle (standard SC corresponds to m = 1). We focus on correlation-sensitive propagation under persistent reuse, and show that this regime produces circuit-dependent stochastic behavior and execution uncertainty patterns that are not captured by stage-wise re-encoded execution alone. To characterize this behavior, we use high-m tail descriptors, including the circuit-dependent coefficient ${\gamma }_c$, as compact indicators of persistent stochastic sensitivity. Across benchmark circuits, persistent execution exhibits reproducible tail regimes and structured cross-circuit variability, while deterministic reduced-precision baselines are used only as trend-consistency references. We further demonstrate adaptive stochastic precision scheduling, where circuit-dependent $(N,m)$ settings satisfy a target fidelity with reduced stochastic workload. These results position persistent ISC as a configurable stochastic execution framework for analyzing execution-induced uncertainty propagation and correlation-sensitive behavior in quantum circuits. Full article

Bacteria in the human intestinal tract express more than 46 million genes, suggesting that interbacterial communication and communication with human cells are well-controlled and synchronized. Many papers have been published on quorum sensing (QS) and other forms of bacterial communication, e.g., nanotubes, nanovibrations, and electromagnetism. Autoinducers (AIs) such as AI-1 N-acyl homoserine lactones (AHLs), AI-2 boron-containing furanosyl borate diesters, AI-3 pyrazinone derivatives, a combination of AI-3/Epi (epinephrine)/NE (norepinephrine), auto-inducer peptides (AIPs), and SdiA (suppressor of division inhibition), along with their receptors, have been well-studied. However, little is known about the roles of quantum mechanics, quantum tunneling, and quantum entanglement in bacterial communication. Most proposals are hypothetical and remain conceptual frameworks supported by indirect evidence rather than validated experiments. The wave-like behavior of ions (quantum tunneling) may facilitate crossing potential energy barriers, such as cell membranes, in concert with protein channels. If this is indeed the case, ions in a quantum-tunneling state would, hypothetically, be able to pass through any part of the cell membrane and cell wall. This would, in theory, enhance biochemical reactions, interbacterial communication, and interactions with human cells. The long-range signaling ability of quanta could allow bacterial cells to maintain contact over long distances, modify their metabolic activities, and activate DNA repair systems. The wave-like behavior of subatomic particles and molecules may cause nanovibrations and generate electromagnetic fields. We argue that electrical signals generated within a biofilm by quanta may attract distant cells and enable cross-species communication. We propose a hypothetical “two-pillar” bacterial communication system, i.e., QS and quantum mechanics/tunneling/entanglement (QMTE), and discuss the advantages of combining both. Full article

We explore the generation of photon blockade effect in a Laguerre–Gaussian optorotational system where a Gaussian beam exchanges orbital angular momentum with a rotating spiral phase mirror. In addition to the typical optorotational coupling, we consider the existence of cross-Kerr nonlinearity between the cavity mode and the rotating mirror. We investigate the statistical characteristics of photons by numerically and analytically calculating the second-order correlation function. In particular, we find that the antibunching effect of photons is dominated by the cooperative operation between the optorotational coupling and the cross-Kerr coupling instead of any individual part. The optimal single photon blockade can be achieved in a moderate coupling regime and enhanced due to the presence of cross-Kerr nonlinearity. The dependence of photon blockade effect on the different system parameters is discussed in detail. Our work provides an alternative way to manipulate the photon quantum behaviors in Laguerre–Gaussian optorotational systems, which may find potential applications in quantum information processing and optical communication utilizing the optical orbital angular momentum. Full article

Bacteria are constantly exposed to stress, which intensifies as cells age, nutrients are depleted, and metabolite levels change. As metabolic activity increases, the cytoplasm transitions from a glass-like to a more fluid state, supporting the stochastic (spontaneous) and chaotic (nonlinear and unpredictable) movement of particles. The rate at which suspended particles or those in vacuole-like “cages” move depends on the cytoplasm’s energized and fluidic state. Cells respond to stochastic and chaotic behavior by regulating gene transcription, translation, and post-translational modifications. These stochastic and chaotic reactions generate a liquid–liquid phase separation (LLPS), causing particles to separate. This produces a dynamic force that drives cytoplasmic “turnover”. Internal and external physicochemical changes are monitored by chemoreceptors on the cell surface and embedded in the cell membrane, which activate transcriptional regulators to control gene expression, modulate enzymatic fluctuations, and regulate post-translational modifications. Sentience may also arise from the quantum-like behavior of ions, electrons, neutrons, and protons (tunneling and entanglement) and from hyperstructures that drive complex enzymatic reactions. This is, however, a highly debated topic. We argue that bacteria are conscious and do not rely solely on phosphorylation states, as in two-component systems (TCSs), but also on other cytoplasmic dynamics. We provide several examples to support the argument. It is, however, important to note that bacterial consciousness cannot be compared to that of higher life forms with a central nervous system. We refer to bacteria’s awareness of their environment as sentience and define bacterial sentience as the ability to respond to external stimuli and to reactions within a dynamic cytoplasm, thereby transferring signals either directly or via signal transduction pathways to turn gene expression on or off. We also point out that stochastic/chaotic randomness keeps the cytoplasm in a permanently dynamic, flexible, and stochastic state, safeguarding the cell against sudden, unpredictable environmental changes. Full article

Temporally correlated flux-induced phase noise can influence superconducting-quantum-circuit execution in ways that are not fully captured by uncorrelated, memoryless, or gate-averaged noise models. In this work, we develop an execution-oriented, circuit-level workflow for modeling and evaluating such effects. The workflow combines source-specific circuit-level noise components with a phenomenological segmented correlation-time construction for flux-induced phase noise, thereby enabling explicit control of a tunable correlation-time parameter ${\tau }_c$ within a composite circuit-level noise model. Using a single-qubit Carr–Purcell–Meiboom–Gill (CPMG) sequence and standard randomized benchmarking as the representative single-qubit circuit settings, we evaluate how circuit outputs respond to temporally correlated flux-induced phase noise under otherwise matched simulation conditions. The results show that temporally correlated flux-induced phase noise produces circuit-level behavior that differs qualitatively from uncorrelated or memoryless descriptions, and that its impact is governed jointly by the correlation-time parameter ${\tau }_c$, the temporal structure of the circuit, and the way in which the circuit samples the noise. The proposed workflow provides a circuit-level framework for analyzing temporally correlated noise in superconducting quantum computing. Full article

Lignin-derived carbon dots (CDs) are promising sustainable fluorescent nanomaterials for environmental sensing, yet precise regulation of their emission behavior and ion-recognition selectivity remains challenging. Herein, a solvent-free precursor–structure–engineering strategy was developed to prepare lignin-derived CDs with tunable photoluminescence and selective metal-ion sensing. Industrial alkali lignin, lysine, and oxalic acid were used as the carbon source, nitrogen source, and carbonization promoter, respectively, while cysteine, histidine, and p-phenylenediamine were introduced as functional precursors. The resulting C-CDs, H-CDs, and P-CDs showed distinct optical and sensing properties. H-CDs exhibited the highest photoluminescence quantum yield of 50.98%, attributed to enhanced graphitic nitrogen formation and electronic conjugation. P-CDs displayed a red-shifted emission at approximately 573 nm due to extended π-conjugated domains. Moreover, C-CDs, H-CDs, and P-CDs showed preferential fluorescence responses toward Fe³⁺, Cu²⁺, and Ag⁺, with detection limits of 0.26, 0.05, and 0.11 μM, respectively. The quenching behavior was inconsistent with a dominant dynamic collisional process and was instead associated primarily with metal–surface interactions. This work clarifies the precursor–structure–property relationship and provides a sustainable route for designing lignin-derived fluorescent probes. Full article

Developing sustainable lithium-ion batteries (LIBs) requires binder–carbon interfaces that combine mechanical compatibility, interfacial cohesion, and reduced environmental impact. In this work, density functional theory calculations were used to evaluate the interactions of representative binder monomers acrylonitrile (AN), pyrrole (PY), vinylidene fluoride (VDF), and tetrafluoroethylene (TFE) with pristine graphene and chitosan-functionalized graphene oxide (GO/chitosan). Structural, energetic, electronic, and topological features were analyzed using counterpoise-corrected interaction energies, frontier-orbital descriptors, molecular electrostatic potential maps, projected density of states, noncovalent interaction analysis, and quantum theory of atoms in molecules topology. Final interaction energies were obtained at the M06-2X/def2-TZVP level with Boys–Bernardi counterpoise correction to provide a more robust description of weak noncovalent adsorption. Most binder–surface interactions fall within a weak, near-thermoneutral adsorption regime. On pristine graphene, AN and PY exhibit weakly favorable adsorption, with minimum counterpoise-corrected interaction energies of −3.13 and −2.10 kcal mol⁻¹, respectively, whereas TFE and VDF show orientation-dependent, near-neutral behavior. GO/chitosan introduces oxygen-containing and amino functionalities that modify the adsorption balance, particularly for selected perpendicular configurations of fluorinated monomers, although the net stabilization remains modest. NCI, QTAIM, MEP, and PDOS analyses indicate that surface functionalization increases the chemical heterogeneity and directionality of local contacts; however, these local descriptors do not necessarily translate into strong global adsorption energies. Overall, the results identify GO/chitosan as a chemically tunable interface for binder–carbon compatibility in LIB electrodes and demonstrate the importance of triple-ζ, counterpoise-corrected calculations for evaluating weak binder–surface interactions. Full article

Van der Waals indium selenide is a promising material for next-generation optoelectronics due to its thickness-dependent band structure and high carrier mobility. Here, we investigate the optical properties of size-selected liquid-phase exfoliated γ-InSe nanosheets. The dispersions, composed of flakes with lateral dimensions below 100 nm, exhibit pronounced structural disorder and size-dependent optical behavior. Absorbance spectroscopy reveals systematic changes across size-selected fractions, enabling the extraction of quantitative metrics for estimating nanosheet lateral size and layers number. In addition, stability studies demonstrate significant degradation under ambient conditions, which is accelerated at elevated temperatures. Photoluminescence measurements on nanosheets exfoliated under inert conditions show broad, asymmetric emission with a clear blue-shift for smaller flakes, reflecting quantum confinement and dielectric screening effects. The emission characteristics further indicate a dominant contribution from localized states associated with disorder. These findings provide insight into the structure–property relationships in liquid-phase exfoliated γ-InSe and highlight its potential for solution-processed optoelectronic applications. Full article