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This paper presents a quantum system designed to generate random, phase-manipulated emissions. A key feature of the proposed system is its ability to create a controllable electromagnetic center. To achieve this, the architecture utilizes two synchronized sources positioned at distinct spatial locations. A method is introduced where Quantum-generated keys are used to form a random sequence in real time to control digital phase manipulators. A block diagram of a quantum system for generating random phase-manipulated emissions with a controllable electromagnetic center has been developed that enables control of the main operating frequency, the length of the additionally generated random sequences controlling the modulations, the frequencies and phases of the emissions, the period and start of phase manipulations, as well as the power of the signals emitted by each of the channels. This way ensures uniformity or a controllable difference in the signals emitted by the two sources of the system upon their arrival at a predetermined point in space. A laboratory prototype of the quantum system has been developed, and tests have been conducted to confirm the feasibility of the proposed method and block diagram. The proposed research refers to a case of phase manipulation of transmitted signals with a preset clock frequency. The theoretical and technical solutions presented in the material can also be used to create systems with randomly frequency-manipulated signals, as well as systems in which the manipulation periods change randomly, determined by random quantum keys generated in real time.

High-valence redox-active ions, exemplified by species such as Fe3+, Cr(vi), Mn(vii), and Ag+, pose fundamental challenges for conventional sensing and recognition platforms due to their intrinsic chemical aggressiveness, narrow stability windows, and propensity for uncontrolled redox transformations. In this review, these chemically aggressive high-valence ions are the primary focus, while more moderately oxidizing species such as Cu2+ are referenced only as comparative benchmarks for shifting MXene quantum dot (MQD) responses within a broader redox-activity spectrum. Despite the rapid progress in nanomaterial-based probes, a unified framework that connects ion valence chemistry, redox constraints, and nanoscale material design is still lacking. Here, we present the first comprehensive review that systematically integrates the thermodynamic and kinetic behaviors of high-oxidation-state ions with quantum confinement - driven redox modulation specifically in MXene quantum dot (MQD) systems. This review begins by establishing the valence-driven reactivity windows that govern the accessibility and instability of high-valence ions, independent of specific material classes. Then, it elucidates how quantum confinement fundamentally reshapes redox responsiveness by discretizing energy states, localizing charge carriers, and amplifying surface-dominated interactions. Building on this foundation, MQDs are examined as redox-programmable platforms capable of translating aggressive ion reactivity into controlled optical signals and multifunctional responses, including detection, validation, and chemical intervention. Rather than emphasizing record detection limits, this review highlights design rules that govern when redox activity enhances functionality and when it undermines stability and interpretability. By reframing redox behavior as a programmable design parameter, this work provides a conceptual roadmap for next-generation adaptive sensing and remediation platforms targeting chemically complex, high-valence ion systems.

The use of Bohmian mechanics as a practical tool for modeling non-relativistic quantum phenomena of matter provides clear evidence of its success, not only as a way to interpret the foundations of quantum mechanics, but also as a computational framework. In the literature, it is frequently argued that such a realistic view-based on deterministic trajectories-cannot account for phenomena involving the "creation" and "annihilation" of photons. In this paper, by revisiting and rehabilitating earlier proposals, we show how quantum optics can be modeled using Bohmian trajectories for electrons in physical space, together with well-defined electromagnetic fields evolving in time. By paying special attention to an experimental scenario demonstrating partition noise for photons, and to how the Born rule emerges in this context, the paper pursues two main goals. First, it validates the use of this simple Bohmian framework for pedagogical and computational purposes in understanding and visualizing quantum electrodynamics phenomena. Second, given that measurements are ultimately indicated on matter pointers, it clarifies what it means to measure photon or electromagnetic-field properties, even when they are considered non-ontic elements.

National Metrology Institutes are advancing quantum electrical standards by transitioning from traditional Gallium Arsenide heterostructures to graphene-based quantum Hall devices. This major shift continues to leverage the 2018 revision of the International System of Units (SI), which sets a connection between fundamental constants of nature and calibration of weights and measures. Graphene offers more relaxed operating parameters due to its unique electronic properties, and this ultimately translates to reduced equipment costs and complexity. These improvements can make quantum electrical standards more accessible for broader adoption beyond primary metrology laboratories. Significant progress in epitaxial graphene growth and device fabrication has led to the development of quantum Hall array resistance standards, which essentially interconnect multiple graphene Hall elements, providing a wider range of quantized resistance values and shortening the calibration chain for various applications. Recent advancements indicate that the use of star-mesh configurations achieve even higher quantized resistance values, promising a more flexible and universal quantum electrical reference.

Holography provides comprehensive characterization of complex light fields, laying the foundation for biological microscopy and precision measurement. Although the amplitude and phase information can be quantitatively analyzed through phase-shifting holography, the additional beam deflection during multistep phase-shifting operations and the shot noise will inevitably reduce the accuracy of holography. Here, a quantum nonlocal holography via multichannel metasurfaces (QNHM) is proposed to achieve high-quality holography under high noise levels. By integrating multiple quantum channels on the metasurface, the projection probabilities of idler photons in four polarization bases are simultaneously measured. Since the spatiotemporal field of signal photons are nonlocally modulated by the polarization of idler photons, the phase-shifting operations is completely avoided. The coincidence measurement greatly filters out the shot noise from the time domain, thereby enhancing the signal-to-noise ratio, image contrast, and accuracy. The proposed QNHM may open up feasible avenues in biomedicine, material analysis, and quantum information processing.

Single-photon emitters (SPEs) are promising building blocks for practical devices in quantum technologies. Traditionally, these systems are excited using off-resonant visible light through their phonon transitions, yet this process remains poorly understood. Here, we explore the interaction of mid-infrared (MIR) excitation with the properties of SPEs in hexagonal boron nitride. Notably, we present a reversible, nondestructive method to enhance emission from blue SPEs using MIR coexcitation. By resonantly driving defect-localized in-plane infrared-active optical phonon modes near 7.3 μm, the MIR field modulates carrier dynamics through a phonon-assisted recombination.This unique feature, not observed previously for defects in solids, is a promising reservoir in a growing toolkit to modulate quantum emitters at room temperature for their use in practical quantum technologies.

Nitrogen-doped MXene quantum dots (N-MQDs) have recently attracted considerable attention as low-dimensional nanomaterials for electrochemical and electrochemiluminescence (ECL) sensing owing to their high electrical conductivity, tunable electronic structure, abundant surface-active sites, and pronounced quantum confinement effects. Nitrogen incorporation enables effective regulation of charge density, energy-level alignment, and radical stabilization, which collectively control electron transfer kinetics and luminescence efficiency. Despite growing interest, a unified mechanistic understanding linking nitrogen doping, signal modulation, and sensing performance remains limited. This review systematically examines the mechanistic principles and signal engineering strategies of N-MQDs in electrochemical and ECL sensing platforms. Key aspects, including electronic structure modulation, charge-transfer pathways, radical-mediated ECL processes, surface-state regulation, and quantum confinement effects, are discussed to establish structure-property-signal relationships. Advanced signal modulation approaches, such as excitation-dependent emission, ratiometric and multichannel detection, temporal and kinetic control, environmental responsiveness, and coreactant-driven amplification, are comprehensively reviewed. Recent applications in biosensing and environmental analysis are also evaluated with emphasis on analytical performance and sensor architectures. This review provides a comprehensive overview of recent advances in N-MQDs for ECL sensing, highlighting synthesis strategies, electronic properties, sensing mechanisms, and emerging applications.

In this paper, to remove the water lock effect in tight gas reservoirs, amphipathic polymer-modified titanium quantum dots (PTQs) were synthesized via in situ polymerization, showing a hyper-branched structure and an excellent synergistic effect with the nonionic fluorocarbon surfactant to break the water lock. The molecular structure, fluorescent property, and micromorphology of the PTQs were obtained. The surface activity and wettability alteration of rock are discussed. Results show that PTQs have zwitterionic hydrophilic groups and the hydrophobic structure of long-chain groups on their molecular structure. PTQ fluid, with a median particle size of 3.6 nm, showed strong green fluorescence and had excellent dispersibility in 50,000 mg/L of standard saline fluid at 120 °C. Additionally, the surface tension decreased to 18.6 mN/m at a PTQ concentration of 0.08%. At a 0.1% concentration, PTQ fluid altered the water wettability of tight sandstone to 67.2°, which resulted in lower capillary resistance. Furthermore, the surfactant (PHPE) had a good synergistic effect with the PTQs to decrease surface tension and alter the wettability of the sandstone surface, leading to lower surface tension and significant amphiphobicity. The strong surface activity of PTQs results from their specific molecular structure, which enables electrostatic attraction, quantum size effects, hydrogen bonding, and van der Waals forces between the inter-polar molecules of PTQs and the surface of sandstone to forcefully eliminate the water lock effect. This study offers key guidance for the development of a high-performance water-lock-breaking agent and application of titanium quantum dots in tight gas reservoirs.

Bolometric detection offers a compelling route to room-temperature mid- and long-wave infrared (MWIR/LWIR) photodetection by measuring temperature-induced conductivity changes in a thermistor element thermally coupled to an absorber. However, conventional thermistor materials such as vanadium oxide (VOx) and amorphous silicon (a-Si) exhibit moderate temperature coefficient of resistance (TCR) values (-2 to -3%/K). Higher TCRs have been achieved using SiGe/Si quantum wells (∼-5%/K), yet these require costly epitaxial growth and further improvements are hindered by lattice mismatch-induced defects. Here, we report a novel thermistor platform based on colloidal quantum dots (CQDs) that circumvents these limitations by exploiting their lattice-mismatch-free nature. By tuning the size and surface chemistry of lead chalcogenide CQDs, we engineer the energetic potential landscape to modulate thermal activation energy, achieving TCR values of up to -9%/K. We further integrate this CQD thermistor with a plasmonic metamaterial absorber (PMA), enabling room-temperature wavelength-selective photodetection across the mid- to long-wave infrared (MWIR/LWIR) spectrum. The bolometer detectors exhibited LWIR response with a time constant of ∼8 ms and room-temperature detectivity approaching 106 Jones at 9 µm, without using microelectromechanical systems (MEMS) technology.

Magneto-fluorescent carbon quantum dots (CQDs) promise compact, dual-readout nanomaterials; however, achieving pronounced photoluminescence alongside magnetic functionality in a simple, scalable formulation remains difficult, especially for emerging doped CQDs. Here, we report Fe-doped carbon quantum dots (Fe-CQDs) as an emerging quantum-dot platform that integrates fluorescence with magnetic-resonance (MR) relaxometry within a single ultrasmall, carbonaceous nanostructure. To enable this, Fe-CQDs are prepared through a straightforward two-step, low-temperature route that uses a magnetic deep eutectic solvent precursor followed by mild carbonization in air at atmospheric pressure. Under UV excitation, the Fe-CQDs display bright blue emission centered at 439 nm, and their optical behavior is characterized by UV-Vis absorption, photoluminescence spectroscopy, and fluorescence microscopy. Meanwhile, dynamic light scattering indicates a narrowly distributed nanoscale hydrodynamic diameter, and X-ray diffraction together with FT-IR supports a carbonaceous framework enriched with oxygenated surface functionalities, consistent with aqueous dispersibility and environmentally responsive photophysics in water, while XPS supports Fe incorporation in an Fe(III)-dominated chemical environment. Importantly, Fe incorporation enables intrinsic MR relaxometric readout, establishing an intrinsic fluorescence/MR dual modality. As a proof-of-concept, Fe-CQDs were tested with a representative per- and polyfluoroalkyl substance (PFAS), showing parallel fluorescence and MR response trends at ppm levels in natural water matrices from Millerton Lake with Stern-Volmer analysis and a NaCl-based ionic strength control. Overall, these results position Fe-CQDs as a versatile magneto-fluorescent nanomaterial for dual-readout screening workflows and motivate future surface engineering and dopant tuning to improve selectivity and expand toward multi-modal readouts.

Graphene-based ion-sensitive field-effect transistors can operate as biosensors by utilizing the formation of an electric double layer at the interface between the electrolyte and the graphene channel, enabling high sensitivity, scalability, and cost-effective fabrication. In this work, we focus on the working principles and current methodologies associated with these devices, making a comparative analysis of different models that describe the electric double layer in the electrolyte, referring to sodium ions (Na+) as a case study for the detection performance of the graphene biosensor, and taking into account the impact of graphene quantum capacitance. Our study addresses the sensitivity of graphene field-effect transistors within the framework of the Gouy-Chapman model, as well as the Stern model, computing device sensitivities of 3200 V/M and 5500 V/M, respectively. By incorporating the impact of graphene's quantum capacitance in the calculations, increased sensitivity up to 5620 V/M was found. The present work shines light on the rationalization of graphene-based biosensors' operation and performance.

2'-5'-Oligoadenylate synthetases (OAS) are crucial innate immune sensors that activate antiviral responses upon detecting viral double-stranded RNA. Understanding the molecular mechanism of OAS is vital for advancing immunomodulatory therapies. This study provides a detailed enzymatic mechanism of the OAS, integrating structural, kinetic, and quantum chemical analyses. Crystallographic data of the OAS1 postreactive complexes shed light on the geometry of OAS1 following product formation and dissociation, the sequential order of product release, and the pivotal role of divalent metal ions in catalysis. Our data reveal the unanticipated involvement of a third metal ion, which may play a transient supporting role in the catalytic cycle. Moreover, they highlight the central role of quantum mechanisms in the OAS function. Strikingly, substituting catalytic Mg2+ with Mn2+ ions increases the substrate binding rate 9-fold and activates OAS for catalysis. The results of this study are pertinent to the OAS/cGAS family of innate immune sensors and offer insights that can be applied to a broader class of nucleotidyltransferases, which play key roles in various biological processes.

Targeting high-performance and high-density application scenarios, this work systematically investigates the performance limits of ultrashort-channel double-gate (DG) MOSFETs based on halogenated borophene within a density functional theory (DFT)-nonequilibrium Green's function (NEGF) quantum transport simulation framework. Key device metrics such as on-current, subthreshold swing, switching delay, and power consumption are analyzed for both n-type and p-type devices under various gate and underlap lengths. The optimal channel material selection and underlap length configuration are explored. Using B4Cl4 and B4Br4 as channel materials for nMOSFET and pMOSFET, respectively, significantly improves the subthreshold performance, ON-OFF ratio, and energy-delay product. Furthermore, selecting appropriate underlap lengths for different gate lengths enables further device performance optimization. These findings provide a crucial theoretical foundation for the material and structural design and optimization of ultrascaled two-dimensional semiconductor transistors in the post-Moore era.

Nitrogen-doped MXene quantum dots (N-MQDs) have recently emerged as versatile nanomaterials for portable sensing owing to their tunable surface chemistry, defect-rich structure, and favorable optical and electrochemical properties. This review presents a chemically driven perspective on the design of N-MQDs, emphasizing how controlled nitrogen incorporation, defect engineering, and surface termination modulation govern their functional behavior in miniaturized sensing systems. Rather than focusing solely on analytical performance, the discussion highlights material-level design principles that enable stable integration of N-MQDs into portable and smartphone-integrated platforms. Key strategies for physical anchoring, spatial organization, optical coupling, and mechanical robustness are critically examined to clarify how nanoscale chemical features translate into reliable platform-level performance. Representative examples of fluorescence-based, electrochemical, and dual-mode sensing architectures are summarized to illustrate the adaptability of N-MQDs across environmental and bioanalytical applications. By connecting chemical design with architectural integration, this review provides a unified framework for developing next-generation MQD-based sensing platforms compatible with decentralized, user-friendly, and smartphone-assisted diagnostics.

Red- and near-infrared (NIR)-emissive quantum dots (QDs) hold great promise in optoelectronic devices, sensors, and biomedicine owing to their advantages of low optical scattering, deep-tissue penetration, and compatibility with advanced photonic technologies. However, the toxicity of conventional cadmium (Cd)- and lead (Pb)-based QDs has led to growing demand for eco-friendly alternatives. Here, we provide a comprehensive review of sustainable classes of red/NIR-emissive QDs, including indium phosphide (InP), I-III-VI chalcogenides (CuInS2, AgInSe, and so on), group-IV (Si, Ge, and SiGe) nanocrystals, and carbon-based QDs (graphene QDs or carbon dots). InP QDs are leading candidates for display technologies due to their high efficiencies and narrow bandwidths in emission properties, enabled by advanced core/shell engineering. In contrast, I-III-VI chalcogenides, group-IV, and carbon-based QDs offer advantages for biocompatible NIR bioimaging, photothermal therapy, and silicon photonics integration. We discuss synthesis strategies for achieving long-wavelength emission, the mechanisms of red/NIR photoluminescence (PL), and representative applications in displays, sensors, and bioimaging. Finally, we outline the remaining challenges, such as large-scale manufacturing and long-term stability, which should be addressed for commercial and clinical viability.

The discovery of quantum dots (QDs) earned a Nobel Prize and has led to widespread applications in research and technology. In this review, we focus on the use of QDs in solid-state solar cells (QDSCs). We begin with an overview of the basic principles of SCs. Then, we discuss how device architecture has developed over recent decades, setting the stage for the final section on fourth-generation solar cells (Perspective section). We also highlight progress in material development, starting with lead- and cadmium-based QDs and progressing to more recent carbon- and perovskite-based QDs. Additionally, we review materials used for electron-transport layers (ETLs) and hole-transport layers (HTLs). The articles also present recent advances in QDSCs across various QD types. In the final section, we recommend that future research focus on three main areas: QD active-layer materials, material interfaces, and device architecture. These efforts could lead to sustainable QDSCs that potentially surpass the Shockley-Queisser (SQ) limit.

Extracting useful information from noisy near-term quantum simulations requires error mitigation strategies. A broad class of these strategies rely on precise characterization of the noise source. We study the robustness of probabilistic error cancellation and tensor network error mitigation when the noise is imperfectly characterized. We adapt an Imry-Ma argument to predict the existence of a threshold in the robustness of these error mitigation methods for random spatially local circuits in spatial dimensions D ≥ 2 : noise characterization disorder below the threshold rate alows for error mitigation up to times that scale with the number of qubits. For one-dimensional circuits, by contrast, mitigation fails at an 𝒪 1 time for any imperfection in the characterization of disorder. As a result, error mitigation is only a practical method for sufficiently well-characterized noise. We discuss further implications for tests of quantum computational advantage, fault-tolerant probes of measurement-induced phase transitions, and quantum algorithms in near-term devices.

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The inherent instability of magic-size clusters (MSCs), stemming from their ultrasmall dimensions, presents a significant challenge for their synthesis and practical application. This study developed a low-temperature synthesis strategy employing a coordination system based on 1-octadecene selenium (ODESe), diphenylphosphine (DPP) and zinc carboxylate precursors, which successfully produced novel ZnSe clusters with excellent thermal and ligand stability. These robust clusters can serve as precursors for the direct transformation into ZnSe quantum dots (QDs) under mild conditions by simply adding a Se precursors. Notably, the resulting cluster-transformed QDs (6.3 nm) are significantly larger in size than those obtained through the conventional hot-injection method (4.3 nm) at the identical reaction temperature, corresponding to a 19 nm redshift in emission. This work not only establishes a new paradigm for synthesis of stable MSCs but also reveals a non-classical growth regime from robust clusters to large-sized QDs, offering profound insights into the nucleation and growth mechanisms of nanocrystals.