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Spintronics, micro/nanofabrication, and the semiconductor industry are undergoing significant transformations, highlighting the need for flexible technologie. This study examines the possibility of integrating topological insulators (TIs), specifically Bi2Te3 thin films (13–191 nm), into flexible spintronic applications through scalable magneto‐sputtering techniques, and investigates how structural organization influences electrical and topological properties through post‐thermal annealing. Films annealed above 250 °C display improved polycrystalline structure, larger crystallites, fewer local defects, and higher a room‐temperature Seebeck coefficient (S) and resistivity (ρ), suggesting decreased bulk electronic contributions. A metastable transport regime is identified in the temperature‐dependent resistivity of films annealed at 300 °C between 20–100 K; in this range, the thinnest film exhibits markedly metallic behavior, signaling the presence of topological surface states (TSS). Magnetoresistance measurements of as‐grown and annealed films, between 3–20 K, demonstrate weak antilocalization. Applying the Hikami‐Larkin‐Nagaoka model, α‐coefficients are found to scale with thickness from 0.5–1, indicating thickness‐controlled coupling of the TSS. Post‐annealing at 300 °C, the phase coherence length, Lϕ, of the thinner films increases, while the temperature dephasing rate shifts from ∼0.7 (as‐grown) to ∼0.5 (post‐annealing), aligning with expected values for 2D TSS. These are encouraging findings for large‐scale manufacturing flexible TI technologies, without sacrificing tunabilit. [ABSTRACT FROM AUTHOR]

The document "Nanoelectronics: Materials, Devices and Applications" explores the field of nanoelectronics, focusing on the manipulation and control of nano-scale materials and devices to address challenges in the semiconductor industry. The document highlights significant breakthroughs in various industries, such as healthcare and energy systems, achieved through the exploration of materials, devices, and their applications in nanoelectronics. It is anticipated that nanoelectronics will replace microelectronics as the mainstay of information technology in the future, impacting human life profoundly. The document includes research articles covering topics like polymers, devices, energy-harvesting, electrons, sensors, and transducers in nanoelectronics, showcasing advancements and potential applications in the field. [Extracted from the article]

Achieving precise electron or spin confinement is essential for the progress of oxide electronics and emerging quantum information processing. While 2D electron confinement is commonly achieved with bare surfaces, heteroepitaxial interfaces, and charged domain walls, its practical application poses challenges, notably by diverse confinement widths, limited material selection, and the lack of freedom of positioning to a desired location within a given material system. Here, with scrutinizing a novel defect structure, the study suggests a new strategy with compelling evidence to trigger electron confinement down to single unit‐cell‐thickness, through geometrically constrained antipolar ordering facilitated by superlattice‐like periodic planar faults in metallic SrFeO3. Employing atomic resolution electron microscopy and density functional theory, the results demonstrate that electrons are confined two‐dimensionally to screen the positive bound charges on head‐to‐head antipolar state boundary, meanwhile oxygen vacancies segregated in the planar faults compensate the negative bound charges on the tail‐to‐tail one, leading to the stabilization of the antipolar ordering. Additionally, distinguished from traditional methods, this approach offers a potential programing capability for achieving precise charge and spin control by regulating planar fault structure at atomic scale. [ABSTRACT FROM AUTHOR]

Owing to the maturity of complementary metal oxide semiconductor (CMOS) microelectronics, qubits realized with spins in silicon quantum dots (QDs) are considered among the most promising technologies for building scalable quantum computers. For this goal, ultra-low-power on-chip cryogenic CMOS (cryo-CMOS) electronics for control, read-out, and interfacing of the qubits is an important milestone. We report on-chip interfacing of tunable electron and hole QDs by a 64-channel cryo-CMOS multiplexer with less-than-detectable static power dissipation. We analyze charge noise and measure state-of-the-art addition energies and gate lever arm parameters in the QDs. We correlate low noise in QDs and sharp turn-on characteristics in cryogenic transistors, both fabricated with the same gate stack. Finally, we demonstrate that our hybrid quantum-CMOS technology provides a route to scalable interfacing of a large number of QD devices, enabling, for example, variability analysis and QD qubit geometry optimization, which are prerequisites for building large-scale silicon-based quantum computers. The integration of quantum dot spin qubits and classical cryogenic microelectronics is important for scaling up silicon-based quantum computers. The authors show that their silicon technology tailored for low-power electronics and low-noise quantum dots enables the integration of classical multiplexers and quantum dot spin qubit devices on the same chip. [ABSTRACT FROM AUTHOR]

Last December 27th, 2023, Ebru Cavlak Aslan et al. have published the article in the Journal "Optical and Quantum Electronics" the article titled "Analysing of different wave structures to the dissipative NLS equation and modulation instability" (Opt Quantum Electron 56:254, 2024. https://doi.org/10.1007/s11082-023-06035-6) where they tried to present analytical solutions of a dissipative nonlinear Schrödinger equation and study the modulational instability of the continuous wave solution of that equation. After analyzing their results, we found a number of shortcomings about both the modulational instability study and the analytical solutions. For analytical solutions, we found that all their found exact solutions were about the standard nonlinear Schrödinger equation and may contain errors/mistakes since at least one of their found dark soliton solutions was done in the region of modulational instability of the standard nonlinear Schrödinger equation. We also found that all their results about the modulational instability were obtained on an erroneous plane wave solution of their model equation, leading thus to obsolete results. It is the aim of the present comment to correct all shortcomings found in that study on the modulational instability. [ABSTRACT FROM AUTHOR]

Quantum electronics operating in the microwave domain are burgeoning and becoming essential building blocks of quantum computers, sensors, and communication devices. However, the field of microwave quantum electronics has long been dominated by the need for cryogenic conditions to maintain delicate quantum characteristics. Here, a solid‐state hybrid system, constituted by a photo‐excited pentacene triplet spin ensemble coupled to a dielectric resonator, is reported for the first time capable of both coherent microwave quantum amplification and oscillation at X band via the masing process at room temperature. By incorporating external driving and active dissipation control into the hybrid system, efficient tuning of the maser emission characteristics at ≈9.4 GHz is achieved, which is key to optimizing the performance of the maser device. The work not only pushes the boundaries of the operating frequency and functionality of the existing pentacene masers but also demonstrates a universal route for controlling the masing process at room temperature, highlighting opportunities for optimizing emerging solid‐state masers for quantum information processing and communication. [ABSTRACT FROM AUTHOR]

The valley degree of freedom in two-dimensional (2D) materials can be manipulated for low-dissipation quantum electronics called valleytronics. At the boundary between two regions of bilayer graphene with different atomic or electrostatic configuration, valley-polarized current has been realized. However, the demanding fabrication and operation requirements limit device reproducibility and scalability toward more advanced valleytronics circuits. We demonstrate a device architecture of a point junction where a valley-chiral 0D PN junction is easily configured, switchable, and capable of carrying valley current with an estimated polarization of ~80%. This work provides a building block in manipulating valley quantum numbers and scalable valleytronics. [ABSTRACT FROM AUTHOR]

Borophene, as a 2D rising eulogizing star, is garnering increasing attention and recognition due to its venerated properties including anisotropic plasmonics, exemplary in-plane elasticity, superconductivity, massless Dirac fermions, high electron mobility, exceptional flexibility, exquisite tunability, and metallic properties across the majority of its structural models. These characteristics make borophene a promising material with diverse implementations like quantum electronics, high-speed low-dissipation devices, gas sensors, and energy storage. Following the landmark synthesis of borophene in 2015, a multitude of scientific endeavors have explored diverse synthesis approaches for producing borophene on a range of substrates. Within, this comprehensive review, we endeavor to present a succinct yet thorough examination of the myriad synthesis approaches employed for borophene fabrication on various substrates. In tandem, we meticulously delineate the merits and demerits inherent to each of these elucidated synthesis techniques. Furthermore, the review encompasses a summary of applications of borophene. Simultaneously, we proffer suggestions, address existing challenges, and discern novel prospects, thus extending an invitation for future exploration in this promising domain of scientific inquiry. [ABSTRACT FROM AUTHOR]

Hybrid superconductor–semiconductor materials systems are promising candidates for quantum computing applications. Their integration into superconducting electronics has enabled on-demand voltage tunability at millikelvin temperatures. Ge quantum wells have been among the semiconducting platforms interfaced with superconducting Al to realize voltage tunable Josephson junctions. Here, we explore Nb as a superconducting material in direct contact with Ge channels by focusing on the solid-state reactions at the Nb/Ge interfaces. We employ Nb evaporation at cryogenic temperatures (∼100 K) to establish a baseline structure with atomically and chemically abrupt Nb/Ge interfaces. By conducting systematic photoelectron spectroscopy and transport measurements on Nb/Ge samples across varying annealing temperatures, we elucidated the influence of Ge out-diffusion on the ultimate performance of superconducting electronics. This study underlines the need for low-temperature growth to minimize chemical intermixing and band bending at the Nb/Ge interfaces. [ABSTRACT FROM AUTHOR]

This study explores defect engineering in 2D materials using ion beam irradiation to modify the electrical and optical properties with potential in advancing quantum electronics and photonics. Helium and neon ions ranging from 5 to 7.5 keV are employed to manipulate charge transport in monolayer molybdenum disulfide (MoS2). In situ electrical characterization occurs without vacuum breakage post‐irradiation. Raman and photoluminescence spectroscopy quantify ion irradiation's impact on MoS2. Small doses of helium ion irradiation enhance monolayer MoS2 conductivity in field‐effect transistor geometry by inducing doping and substrate charging. Findings reveal a strong correlation between the electrical properties of MoS2 and the primary ion used, as well as the substrate on which the irradiation occurred. Using hexagonal boron nitride (h‐BN) as a buffer layer between MoS2 flake and SiO2 substrate yields distinct alterations in electrical behavior subsequent to ion irradiation compared to the MoS2 layer directly interfacing with SiO2. Molecular dynamics simulations and density functional theory provide insight into experimental results, emphasizing substrate influence on measured electrical properties post‐ion irradiation. [ABSTRACT FROM AUTHOR]

Photolithography has been the foundational fabrication paradigm in current high‐performance electronics. However, due to the limitation in fabrication resolution, scaling beyond a 20‐nm critical dimension for metal conductors presents a significant challenge for photolithography. Structural DNA nanotechnology emerges as a promising alternative to photolithography, allowing for the site‐specific assembly of nano‐materials at single‐molecule resolution. Substantial progresses have been achieved in the ultra‐scaled DNA‐based conductors, exhibiting novel transport characteristics and small critical dimensions. This review highlights the structure‐transport property relationship for various DNA‐based conductors and their potential applications in quantum /semiconductor electronics, going beyond the conventional scope focusing mainly on the shape diversity of DNA‐templated metals. Different material synthesis methods and their morphological impacts on the conductivities are discussed in detail, with particular emphasis on the conducting mechanisms, such as insulating, metallic conducting, quantum tunneling, and superconducting. Furthermore, the ionic gating effect of self‐assembled DNA structures in electrolyte solutions is examined. This review also suggests potential solutions to address current challenges in DNA‐based conductors, encouraging multi‐disciplinary collaborations for the future development of this exciting area. [ABSTRACT FROM AUTHOR]

Electrostatically tunable Josephson field-effect transistors (JoFETs) are one of the most desired building blocks of quantum electronics. Applications of JoFETs range from parametric amplifiers and superconducting qubits to a variety of integrated superconducting circuits. Here, we report on graphene JoFET devices fabricated with wafer-scale complementary metal-oxide-semiconductor (CMOS)-compatible processing based on chemical-vapor-deposited monolayer graphene encapsulated with atomic-layer-deposited Al2O3 gate oxide, lithographically defined top gate, and evaporated superconducting Ti/Al source, drain, and gate contacts. By optimizing the contact resistance down to ∼170 Ω μm, we observe proximity-induced superconductivity in the JoFET channels with different gate lengths of 150–350 nm. The Josephson junction devices show reproducible critical current I c tunablity with the local top gate. Our JoFETs are in the short diffusive limit with the I c reaching up to ∼3 µA for a 50 µm channel width. Overall, our demonstration of CMOS-compatible two-dimensional (2D) material-based JoFET fabrication process is an important step toward graphene-based integrated quantum circuits. [ABSTRACT FROM AUTHOR]

In the current work, fabrication of silicon carbide (SiC)/cobalt ferrite (CoFe2O4)/polyvinyl alcohol(PVA) nanostructures was investigated as a promising hybrid nanomaterials to utilize in the advanced optical and nanoelectronics applications. The SiC/CoFe2O4 NPs addition into PVA was created of new nanostructures have excellent optical properties, inexpensive, greater physical and chemical characteristics when compared with other nanocomposites. The structural, morphological and optical characteristics of PVA/SiC/CoFe2O4 films were tested. The structural and morphological characteristics involved Fourier-Transform Infrared spectroscopy and optical microscope. The results confirmed that the absorbance of PVA/SiC/CoFe2O4 films is elevated at Ultraviolet spectrum and near infrared spectrum. The PVA absorbance boosted about 94.6% at λ = 340 nm (UV-S) while the reduce of transmittance about 72.4% when the SiC/CoFe2O4 content reached of 6.3 wt.%. This performance makes the PVA/SiC/CoFe2O4 films are promising nanostructures for UV-shielding and other optical and electronics applications. The energy gap of PVA was decreased from 5.1 to 2.3 eV for allowed transition and from 4.7 to 0.6 eV for transition of forbidden when the SiC/CoFe2O4 NPs content reached of 6.3 wt.%., and these results made the PVA/SiC/CoFe2O4 films are welcomed in the optical and electronics fields. The other optical parameters of PVA were improved with growing SiC/CoFe2O4 NPs content; these results are appropriate for many optical fields. Finally, the attained results indicated that the PVA/SiC/CoFe2O4 films can be useful for promising optical, photonics and electronics applications. [ABSTRACT FROM AUTHOR]

Accurately and instantly estimating the hydrodynamic characteristics in two-phase liquid–gas flow is crucial for industries like oil, gas, and other multiphase flow sectors to reduce costs and emissions, boost efficiency, and enhance operational safety. This type of flow involves constant slippage between gas and liquid phases caused by a deformable interface, resulting in changes in gas volumetric fraction and the creation of structures known as flow patterns. Empirical and numerical methods used for prediction often result in significant inaccuracies during scale-up processes. Different methodologies based on artificial intelligence (AI) are currently being applied to predict hydrodynamic characteristics in two-phase liquid–gas flow, which was corroborated with the bibliometric analysis where AI techniques were found to have been applied in flow pattern recognition, volumetric fraction determination for each fluid, and pressure gradient estimation. The results revealed that a total of 178 keywords in 70 articles, 29 of which reached the threshold (machine learning, flow pattern, two-phase flow, artificial intelligence, and neural networks as the high predominance), were published mainly in Flow Measurement and Instrumentation. This journal has the highest number of published articles related to the studied topic, with nine articles. The most relevant author is Efteknari-Zadeh, E, from the Institute of Optics and Quantum Electronics. [ABSTRACT FROM AUTHOR]

Low‐power nonvolatile memories operating down to deep cryogenic temperatures are important for a large spectrum of applications from high‐performance computing, electronics interfacing quantum computing hardware to space‐based electronics. Despite the potential of Hf0.5Zr0.5O2 (HZO), thanks to its compatibility with complementary metal‐oxide‐semiconductor (CMOS) back‐end‐of‐line processing, only few studies of HZO‐based memory devices down to cryogenic operation temperatures exist. Here, analog ferroelectric memory stack fabrication with 10 nm HZO and their detailed characterization under wide range of pulse amplitudes and frequencies down to 4 K are reported. When operated at temperatures below 100 K, HZO devices can support high amplitude voltage pulses, yielding record high Pr of up to 75µC cm−2 at ±7 Vp (14 Vpp) pulse amplitudes accompanied with frequency‐dependent memory window between 6 and 8 V. Devices show excellent endurance exceeding 109 cycles of ±5 Vp (10 Vpp) and Pr of 30 µC cm−2 without significant degradation of coercive voltages or loss of polarization at cryogenic temperatures. At least 20 reproducible analog states for temperatures below 100 K with almost ideal linearity of intermediate polarization states in both pulse directions is observed, demonstrating the high potential of analog cryogenic ferroelectric memories, essential for on‐line training in in‐memory‐computing architecture. [ABSTRACT FROM AUTHOR]

In this paper, we address various optical soliton solutions and demonstrate the different dynamics of solitary waves to a (3+1)-dimensional nonlinear Schrödinger equation (NLSE) with parabolic law (NLSE) using a newly created powerful and effective method named as the extended generalized Riccati equation mapping method. This technique presents an organized manner to reveal the essential dynamics. There is great significance of the nonlinear Schrödinger equations and their several formulations in numerous fields of science, particularly in nonlinear optics, optical fibers, quantum electronics, and plasma physics. Through the use of numerical simulations and mathematical analysis, we explore the characteristics and behavior of these solitary wave solutions in a variety of scientific contexts. These results demonstrate the essential complexity of the governing equation and yield novel derived solutions. These solutions contribute to a better understanding of nonlinear wave phenomena by highlighting the fundamental dynamics establishing solitary waves in the NLSE. To enhance our wider knowledge, we provide effective graphic representations of the nonlinear wave structures in the derived solutions utilizing a variety of graphs, including 3D, 2D, and density plots. Moreover, a specific transformation has been applied to transform the system into a planar dynamical system, and several phase portraits have been presented to examine its behavior. Furthermore, upon introducing a perturbed term, chaotic behavior has been observed across different parameter values through both two-dimensional and three-dimensional graphics. [ABSTRACT FROM AUTHOR]

The ability to finely tune the properties of magnetic topological insulators (TIs) is crucial for quantum electronics. We studied solid solutions with a general formula GexMn1-xBi2Te4 between two isostructural Z2 TIs, magnetic MnBi2Te4 and nonmagnetic GeBi2Te4 with Z2 invariants of 1;000 and 1;001, respectively. We observed linear x-dependent magnetic properties, composition-independent pairwise exchange interactions, and topological phase transitions (TPTs) between topologically nontrivial phases and the semimetal state. The TPTs are driven purely by the variation of orbital contributions. By tracing the x-dependent Bi 6p contribution to the states near the fundamental gap, the effective spin-orbit coupling variation is extracted. The gapless state observed at x = 0.42 closely resembles a Dirac semimetal above the Néel temperature and shows a magnetic gap below, which is clearly visible in raw photoemission data. The observed behavior demonstrates an ability to precisely control topological and magnetic properties of TIs. Topological insulators with ordered moments of embedded magnetic atoms are viable platforms for quantum electronics, but the practical applications are restricted by the size of their crystals. The authors synthesize a Z2 topological insulator GexMn1-xBi2Te4 in the form of a large crystal with high structural perfection and tunable magnetic and electronic properties. [ABSTRACT FROM AUTHOR]

The ability to finely tune the properties of magnetic topological insulators (TIs) is crucial for quantum electronics. We studied solid solutions with a general formula GexMn1-xBi2Te4 between two isostructural Z2 TIs, magnetic MnBi2Te4 and nonmagnetic GeBi2Te4 with Z2 invariants of 1;000 and 1;001, respectively. We observed linear x-dependent magnetic properties, composition-independent pairwise exchange interactions, and topological phase transitions (TPTs) between topologically nontrivial phases and the semimetal state. The TPTs are driven purely by the variation of orbital contributions. By tracing the x-dependent Bi 6p contribution to the states near the fundamental gap, the effective spin-orbit coupling variation is extracted. The gapless state observed at x = 0.42 closely resembles a Dirac semimetal above the Néel temperature and shows a magnetic gap below, which is clearly visible in raw photoemission data. The observed behavior demonstrates an ability to precisely control topological and magnetic properties of TIs. Topological insulators with ordered moments of embedded magnetic atoms are viable platforms for quantum electronics, but the practical applications are restricted by the size of their crystals. The authors synthesize a Z2 topological insulator GexMn1-xBi2Te4 in the form of a large crystal with high structural perfection and tunable magnetic and electronic properties. [ABSTRACT FROM AUTHOR]

Nonlinear partial integro-differential equations (PIDEs) are applied to present the various practical phenomena in a multitude of sectors of modern science and engineering, especially in optic fiber, quantum electronics, modern physics, and the special field of nonlinear wave motion. Basically, our research demonstrates a way to generate a significant quantity of solutions to these types of two PIDEs. In this research, we have used an efficient mathematical tool namely the generalized G ′ / G -expansion method to acquire the closed form soliton solutions for the (2 + 1)-dimensional first integro-differential Kadomtsev–Petviashivili (KP) hierarchy equation and the (2 + 1)-dimensional second integro-differential KP hierarchy equation utilizing a code likely Mathematica. The explicit closed form soliton solutions of these two PIDEs are found in the pattern of trigonometric, hyperbolic, and rational functions which are compared to all the well-known results that are yielded in the paper. We attain solutions that are graphically displayed in addition to physically described in 3D structure, contour, and 2D, such as a bell-shaped soliton, a singular bell-shaped soliton, and some kink-shaped solitons. As far as the authors' wisdom, the outcomes of these problems gained by the offered expansion method are renewed closed form solitary wave and investigated here for the first time. The analysis of obtained results will be able to provide a constructive explanation of the physical phenomena in optical physics and engineering. [ABSTRACT FROM AUTHOR]

Abstract Quantum electronics operating in the microwave domain are burgeoning and becoming essential building blocks of quantum computers, sensors, and communication devices. However, the field of microwave quantum electronics has long been dominated by the need for cryogenic conditions to maintain delicate quantum characteristics. Here, a solid‐state hybrid system, constituted by a photo‐excited pentacene triplet spin ensemble coupled to a dielectric resonator, is reported for the first time capable of both coherent microwave quantum amplification and oscillation at X band via the masing process at room temperature. By incorporating external driving and active dissipation control into the hybrid system, efficient tuning of the maser emission characteristics at ≈9.4 GHz is achieved, which is key to optimizing the performance of the maser device. The work not only pushes the boundaries of the operating frequency and functionality of the existing pentacene masers but also demonstrates a universal route for controlling the masing process at room temperature, highlighting opportunities for optimizing emerging solid‐state masers for quantum information processing and communication.

Moiré lattices formed in twisted and lattice-mismatched van der Waals heterostructures have emerged as a platform to engineer the novel electronic and excitonic states at the nanoscale. This Perspective reviews the materials science of moiré heterostructures with a focus on the structural properties of the interface and its structural–property relationships. We first review the studies of the atomic relaxation and domain structures in moiré superlattices and how these structural studies provide critical insights into understanding the behaviors of quantum-confined electrons and excitons. We discuss the general frameworks to manipulate moiré structures and how such control can be harnessed for engineering new phases of matter and simulating various quantum phenomena. Finally, we discuss routes toward large-scale moiré heterostructures and give an outlook on their applications in quantum electronics and optoelectronics. Special emphasis will be placed on the challenges and opportunities of the reliable fabrication and dynamical manipulation of moiré heterostructures. [ABSTRACT FROM AUTHOR]

The crystallization of amorphous solids impacts fields ranging from inorganic crystal growth to biophysics. Promoting or inhibiting nanoscale epitaxial crystallization and selecting its final products underpin applications in cryopreservation, semiconductor devices, oxide electronics, quantum electronics, structural and functional ceramics, and advanced glasses. As precursors for crystallization, amorphous solids are distinguished from liquids and gases by the comparatively long relaxation times for perturbations of the mechanical stress and for variations in composition or bonding. These factors allow experimentally controllable parameters to influence crystallization processes and to drive materials toward specific outcomes. For example, amorphous precursors can be employed to form crystalline phases, such as polymorphs of Al2O3, VO2, and other complex oxides, that are not readily accessible via crystallization from a liquid or through vapor-phase epitaxy. Crystallization of amorphous solids can further be guided to produce a desired polymorph, nanoscale shape, microstructure, or orientation of the resulting crystals. These effects enable advances in applications in electronics, magnetic devices, optics, and catalysis. Directions for the future development of the chemical physics of crystallization from amorphous solids can be drawn from the structurally complex and nonequilibrium atomic arrangements in liquids and the atomic-scale structure of liquid–solid interfaces. [ABSTRACT FROM AUTHOR]

Controlled epitaxial growth of 4H‐SiC is essential for advancing both power electronics and quantum technologies. This study explores how different carbon sources—methane and propane—affect the surface morphology of these epitaxial layers. By varying C/Si ratios and using the two mentioned hydrocarbons as the carbon source in chloride‐based epitaxial growth of 4H‐SiC layers, it is unveiled that methane results in an exceptionally smooth surface. However, it pronounces surface irregularities such as short step bunching and dislocation‐related etch pits. Moreover, methane amplifies the overgrowth of triangular defects with the 4H polytype. In contrast, the introduction of propane causes a step‐bunched surface together with inclined line‐like surface morphological defects. Notably, a majority of the triangular defects exhibit a pure 3C character without an overgrown 4H polytype. It is shown that these outcomes could be attributed to different sticking coefficients and diffusivity of the molecular species resulting from different carbon sources on the 4H‐SiC surface during the epitaxial growth. This research also uncovers the underlying origins and mechanisms responsible for various surface morphological defects. [ABSTRACT FROM AUTHOR]

In this work, the switching mechanism of a molecular redox switch due to the application of an external electric field (along the X axis) was studied using density functional theory (DFT/TD-DFT), quantum theory of atom-in-molecule and Landauer theory. In this regard, some electronic, vibrational and optical properties of this molecular switch are calculated. In addition, the current–voltage (I–V) diagram, as well as Joule-like and Peltier-like ntermolecular phenomenological coefficients of this molecular switch, were calculated using Onsager linear Force-Flux law. When the electric field is applied along the X-axis (Ex) and its intensity increases to 40 × 10–4 a.u, the studied molecular switch is turned on. In addition, the results of this study showed that applying an external electric field has a significant effect on the optical properties of this designed molecular switch. [ABSTRACT FROM AUTHOR]

The current work aims to produce of new nanostructured films from cobalt oxide (Co2O3)/iron oxide (Fe2O3) nanostructures doped polyvinyl alcohol (PVA) as a promising nanocomposites materials to utilize in numerous quantum electronics and optical nanodevices. The structure, optical, and electronic characteristics of PVA/Co2O3/Fe2O3 nanostructured films were investigated. The structure properties included optimization, FTIR and optical microscope. The optical characteristics results indicated that the absorption increased of 91.3% at UV-spectra (λ = 360 nm) with rising of the Co2O3/Fe2O3 NPs content to 5.7 wt%. The energy gap decreased of 55.3% when the Co2O3/Fe2O3 NPs content reached of 5.7 wt% where it reduced from 4.03 to 1.8 eV, this performance make them appropriate for may optoelectronics nanodevices like transistors, photovoltaic cell, electronic gates, diodes and other applications. The optical parameters: absorption coefficient (α); refractive index (n); extinction coefficient (k); real (ε1) and imaginary (ε2) dielectric constants and optical conductivity (σop) of PVA enhanced with an increase in the Co2O3/Fe2O3 NPs content. Finally, obtained results showed that the PVA/Co2O3/Fe2O3 nanostructured films have excellent electronic and optical properties which make them as promising nanomaterials to employ in many quantum electronics and optical nanodevices. [ABSTRACT FROM AUTHOR]

The current research aims to create of novel nanostructured films from silicon sarbide(SiC)/cerium oxide (CeO2) doped polyvinyl alcohol (PVA) as a promising nanocomposites materials to utilize in numerous quantum electronics and optical nanodevices. The fabricated nanostructures have great properties compared of other nanomaterials comprised few cost, excellent optical characteristics, flexible and lightweight. The structure, optical, and electronic features of PVA/SiC/CeO2 nanostructures were investigated. The structure properties included optimization, FTIR and optical microscope (OM). The optical characteristics were tested at wavelength ranged (200–800) nm. The optical characteristics results indicated that the absorbance of PVA rises about 76.9% at (λ = 240 nm, UV-spectra) while rises of 87% at (λ = 540 nm, VIS-spectra) when the SiC/CeO2 NPs content reached of (5.7 wt%).%. The energy gap decreased when the SiC/CeO2NPs content reached of 5.7wt% where it reduced from 4.5 to 2.7 eV, this performance make them appropriate for may optoelectronics nanodevices like transistors, photovoltaic cell, electronic gates, lasers, diodes and other applications. The optical parameters of PVA; with an increase in the SiC/CeO2 NPs content, the optical conductivity(σop), real (ε1) and imaginary (ε2) dielectric constants, absorption coefficient (α), refractive index (n), extinction coefficient (k), and other properties improved. Finally, the obtained results demonstrated that the PVA/SiC/CeO2 nanostructures are promising nanomaterials to employ in many quantum electronics and optical nanodevices. [ABSTRACT FROM AUTHOR]

The Quantum Dot Cellular Automata (QCA) is an emerging quantum electronics technology in which quantum cells are the fundamental building blocks. In this work, a Binary to Gray (BTG) code converter design is proposed and implemented using the QCA Designer Tool. This code converter design requires fewer cells than earlier designs and also increases the converter’s implementation bit size to five. The primary objective of this proposal is to introduce a BTG code converter design that excels in temperature stability and energy efficiency. The cell count in the proposed converter design for two-bit, three-bit, and four-bit is decreased by 68.55 %, 66.52 %, and 67.77 %, respectively and the overall area improved by 46.15 %, 52.17 %, and 57.58 % for 2- bit,3-bit and 4-bit, respectively by considering a latency of 0.75. The five-bit BTG has an area of 0.20 µm2 with a cell count of 141 and a latency of 0.75. To validate the functionality of the proposed design, extensive simulations were carried out using the QCA Designer tool, QCA DesignerE tool, and QCA Pro tool respectively.

The article focuses on the development and application of colloidal quantum dots (CQDs), tracing their historical discovery and the advancement of synthesis methods, particularly high-temperature colloidal synthesis (HTCS). It discusses the physical mechanisms behind quantum size effects, the challenges in achieving high-quality luminescent properties, and new universal laws of photoluminescence applicable to CQDs.

Significant progress has been achieved with silicon carbide (SiC) high power electronics and quantum technologies, both drawing upon the unique properties of this material. In this Perspective, we briefly review some of the main defect characterization techniques that have enabled breakthroughs in these fields. We consider how key data have been collected, interpreted, and used to enhance the application of SiC. Although these fields largely rely on separate techniques, they have similar aims for the material quality and we identify ways in which the electronics and quantum technology fields can further interact for mutual benefit. [ABSTRACT FROM AUTHOR]

Optimal control of qubits requires the ability to adapt continuously to their ever-changing environment. We demonstrate a real-time control protocol for a two-electron singlet-triplet qubit with two fluctuating Hamiltonian parameters. Our approach leverages single-shot readout classification and dynamic waveform generation, allowing full Hamiltonian estimation to dynamically stabilize and optimize the qubit performance. Powered by a field-programmable gate array (FPGA), the quantum control electronics estimates the Overhauser field gradient between the two electrons in real time, enabling controlled Overhauser-driven spin rotations and thus bypassing the need for micromagnets or nuclear polarization protocols. It also estimates the exchange interaction between the two electrons and adjusts their detuning, resulting in extended coherence of Hadamard rotations when correcting for fluctuations of both qubit axes. Our study highlights the role of feedback in enhancing the performance and stability of quantum devices affected by quasistatic noise. Real-time adaptive control of a qubit has been demonstrated but limited to single-axis Hamiltonian estimation. Here the authors implement two-axis control of a singlet-triplet spin qubit with two fluctuating Hamiltonian parameters, resulting in improved quality of coherent oscillations. [ABSTRACT FROM AUTHOR]

The goal of current work includes the creation of new nanohybrid structures from SiC–In2O3 nanostructures doped (PS) as a potential nanomaterials have superior qualities, such as low cost, superior optical properties, flexibility, and lightweight nature to be used in a variety of optical and quantum electronic devices. The optical, electronic and structural properties of PS–SiC–In2O3 nanostructures' were examined. The structural properties comprised: FTIR, optical microscopy, and optimization. The findings of the optical characteristics showed that an increase of 3.6% SiC–In2O3 NPs lead to an increase of 83.3% in the absorption at λ = 560 nm. When the SiC–In2O3 NPs content reached 3.6%, the energy gap shrank from 3.7 to 2.62 eV. The optical factors of PS increased with a rise in the SiC–In2O3 NPs content are including the dielectric constants' real (ε1) and imaginary (ε2) components, optical conductivity (σop), absorption coefficient (α), refractive index (n), and extinction coefficient (k). The PS–SiC–In2O3 nanostructures are potentially useful nanomaterials for use in a variety of quantum electronics and optical nanodevices, according to the final results. [ABSTRACT FROM AUTHOR]

Since their introduction, all-optical spectroscopy techniques based on attosecond radiation have gained the attention of the scientific community because of their energy and time resolution, combined with an easier experimental implementation with respect to other approaches based on charged particle detection. At the present time, almost ten years after the first application to a solid sample, attosecond transient absorption spectroscopy (ATAS) and attosecond transient reflection spectroscopy (ATRS) have established as powerful tools to investigate how electrons can be excited and accelerated in matter with short light pulses, a key requisite to establish ultrafast switches in quantum electronics and overcome the current rate of data processing and information encoding. In this work, we start with a historical overview of the first pioneering experiments to then introduce the fundamentals of both techniques. We conclude by discussing the current challenges and the possible future developments that are expected to bring ATAS and ATRS beyond their state of the art. [ABSTRACT FROM AUTHOR]

Relevance of recent research is important for scientists and journals reporting research results. There are many sources of prognoses and one of them is the Report of European Commission "Looking into the R&I future priorities 2025-2027". It predicts the importance of the following areas for users: healthcare, energy, climate, sustainability and digitalization. The Ukrainian journal Semiconductor Physics, Quantum Electronics and Optoelectronics (SPQEO) actually focuses on these areas and contributes to the development of related knowledge. Monitoring of last SPQEO issues shows some interesting results: (i) the effect of local field amplification, which causes emergence of ponder motive forces acting on viruses until destruction of viral envelopes; (ii) the methods of malignant tumors treatment taking into account their genesis mechanisms and focusing on correction of definite pathogenesis components, while being nontoxic for other organs and tissues; and (iii) manipulation of the spectral characteristics of a "polycarbonate matrix - gold nanostructures - HTTH dye" system due to influence of gold nanostructures. SPQEO paid attention to the improvement of solar cells (SCs) by considering physical effects such as the effect of space charge region (SCR) recombination on the key characteristics of high-efficiency silicon solar cells, such as photovoltaic conversion efficiency and open-circuit voltage, is not only dependent on the charge-carrier lifetime in the SCR, but also on the ratio of hole-to-electron-capture cross section, σp/σn. Nontraditional SCs were also considered: SCs with perovskite thin films, SCs comprising CdS/CIGS heterojunctions, and vitamin B12-patterned silicon hybrids based SCs. Moreover, SPQEO also covers research results in the fields of quantum devices, diamondlike and oxide films, and light-emitting diodes. [ABSTRACT FROM AUTHOR]

Solid-state quantum emitters need accurate nanofabrication platforms with high process yields in order to be used in practical quantum information technologies. Self-assembled semiconductor quantum dots have shown to be among finest choices to fulfil the requirements of a variety of innovative quantum photonic devices due to their exceptional emission features. The aim of this research is to develop quantum electronic material nanofabrication in manufacturing industry based on spectroscopy techniques. Using optical quantum electronics, IR absorption spectroscopy, Raman scattering, and surface-enhanced Raman scattering for nanomaterial characterization, the proposed model for manufacturing industrial material nanofabrication is described here. Here, we demonstrate the nanofabrication of polymer nanostructures with better than 100 nm spatial resolution, chemical identification at nanometer scale, and nanometer-scale chemical imaging. When employing either band, particularly spectrally sharp band at 1000 cm−1, inverse ratio of these typical death periods is known as the "cell death enhancement factor." These findings significantly support the prospective future application of this approach to investigate the effectiveness, dynamics, and molecular processes of different manufacturing industry defect detection. [ABSTRACT FROM AUTHOR]

GaN technology is not only gaining traction in power and RF electronics but is also rapidly expanding into other application areas including digital and quantum computing electronics. This paper provides a glimpse of future GaN device technologies and advanced modeling approaches that can push the boundaries of these applications in terms of performance and reliability. While GaN power devices have recently been commercialized in the 15–900 V classes, new GaN devices are greatly desirable to explore both higher-voltage and ultra-low-voltage power applications. Moving into the RF domain, ultra-high frequency GaN devices are being used to implement digitized power amplifier circuits, and further advances using the hardware–software co-design approach can be expected. On the horizon is the GaN CMOS technology, a key missing piece to realize the full-GaN platform with integrated digital, power, and RF electronics technologies. Although currently a challenge, high-performance p-type GaN technology will be crucial to realize high-performance GaN CMOS circuits. Due to its excellent transport characteristics and ability to generate free carriers via polarization doping, GaN is expected to be an important technology for ultra-low temperature and quantum computing electronics. Finally, given the increasing cost of hardware prototyping of new devices and circuits, the use of high-fidelity device models and data-driven modeling approaches for technology-circuit co-design are projected to be the trends of the future. In this regard, physically inspired, mathematically robust, less computationally taxing, and predictive modeling approaches are indispensable. With all these and future efforts, we envision GaN to become the next Si for electronics. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "On some novel bright, dark and optical solitons to the cubic-quintic nonlinear non-paraxial pulse propagation model" published in the journal Optical & Quantum Electronics. The authors apologize for a typesetting error in the equations in the original publication. The corrected equations are provided for four different cases, along with corresponding graphs. The document includes mathematical formulas and does not provide any additional information beyond the correction. [Extracted from the article]

The design of a solid-state quantum processor is nowadays a hot research topic in microelectronics. Like the logic gates in a classical processor, quantum gates serve as the fundamental building blocks for quantum processors. The main goal of the present paper is to deduce the matrix of the main one- and two-qubit quantum gates from the Schrödinger equation. The mathematical formalism is kept as comfortable as possible for electronics engineers. This paper does not cover topics such as dissipations, state density, coherence, and state purity. In a similar manner, this paper also deals with the quantum nature of a quantum processor by leveraging the concept of a finite-state machine, which is a background notion for any electronics engineer. [ABSTRACT FROM AUTHOR]

This study objects to synthesize of silicon carbide (SiC)/barium titanate (BaTiO3) nanostructures doped polymethylmethacrylate (PMMA)/polyethylene oxide (PEO) blend as a promising nanosystems to apply in photonics and optics applications with few cost, flexible, lightweight, and excellent optical properties compared to other nanosystems. The morphological and optical properties of PMMA/PEO/SiC/BaTiO3 nanostructures were explored. The morphology of films surface for PMMA/PEO/SiC/BaTiO3 nanostructures was investigated by optical microscope(OM) and scanning electron microscope (SEM). The optical characteristics were examined at wavelength range from 240 to 840 nm. The OM and SEM analysis were indicated to the excellent homogeneous of SiC/BaTiO3 NPs within the PMMA/PEO matrix. The optical characteristics of PMMA/PEO/SiC/BaTiO3 nanostructures demonstrated that the absorbance(A) increased of 45.7% at UV-λ = 280 nm, 53.3 at VIS-λ = 480 nm and 57.4% at IR-λ = 780 nm when the content of SiC/BaTiO3 NPs reached of 6.4 wt.%. The energy band gap decreased for allowed from 3.4 to 1.9 eV and from 2.8 to 1.7 eV for forbidden indirect transitions. The other optical parameters: absorption coefficient (α), extinction coefficient (k), refractive index (n), real (ε1) and imaginary(ε2) parts of dielectric constants and optical conductivity (σop) of PMMA/PEO blend enhanced with rising of the SiC/BaTiO3 NPs, this performance lead to create the PMMA/PEO/SiC/BaTiO3 nanostructures as a superior optical nanomaterials for optical and electronics approaches. Finally, the excellent obtained results make the PMMA/PEO/SiC/BaTiO3 nanostructures are welcomed in various optical and photonics devices. [ABSTRACT FROM AUTHOR]

As the number of qubits in quantum computing increases, the scalability of existing qubit circuit structures and control systems may become insufficient for large-scale expansion and high-fidelity control. To address this challenge, we propose a behavioral-level model of a superconducting qubit and its control electronics, followed by a co-simulation to evaluate their performance. In this paper, we present the modeling process, simulation procedure, and resulting design specifications for the qubit control system. Our co-simulation approach utilizes MATLAB and Simulink, enabling us to derive critical circuit design specifications, such as the required Digital-to-Analog Converter (DAC) resolution, which should be 8 bits or higher, to achieve high-fidelity control. By taking into account factors such as DAC sampling rates, integral and differential nonlinearities, and filter characteristics, we optimize the control system for efficient and accurate qubit manipulation. Our model and simulation approach offer a promising solution to the scalability challenges in quantum computing, providing valuable insights for the design of large-scale superconducting quantum computing systems. [ABSTRACT FROM AUTHOR]

The Ukrainian journal Semiconductor Physics, Quantum Electronics and Optoelectronics (SPQEO) was launched in 1998 artificially combining three main areas of scientific activity inherent to the V. Lashkaryov Institute of Semiconductor Physics of the National Academy of Sciences of Ukraine, namely semiconductor physics, quantum electronics and optoelectronics. After a decade this artificial base turned into some kind of organic symbiosis, namely: (i) the main optoelectronic systems are based on semiconductor devices, for example, fiber-optic networks; (ii) semiconductor lasers dominate in a huge number of applications in quantum electronics; (iii) semiconductor physics proposes new types of LEDs with extremely high efficiency, and so on. This article is dedicated to the 25th anniversary of SPQEO. According to the Google Scholar Citation statistics, above 1680 articles cited more than 7350 times in total were published in the journal from 1998 to 2023. The statistics of references of journal articles and the scientific areas of the most cited articles are presented. [ABSTRACT FROM AUTHOR]

Comprehensive inquisition of wireless communication with flexible quantum electronics and physics can be considered as one of the blooming technology. Quantum Cryptography which extends from combination of quantum electronics and physics is one of the best technology that helps to transfer data securely between various user's, due to its rudimentary concept of Quantum Key Distribution (QKD). There are two major concerns in the communication. The first concern is for the data transmission which is frequently carried out through some entity of the cellular network such as Home subscriber Server (HSS) or Gateway (GW), and Evolved Node B(eNB), which is inadvisable to preserve confidentiality of the message. The second concern is, device-to-device (D2D) communication via prose function which is relatively a threat affected path that can be easily affected by the man in the middle (MitM) attack, message drop attack, replay attack, denial of service (DoS) attack, impersonation attack.. To mitigate these threats, this research work is proposing a Secure Authentication Protocol (SAP). The proposed SAP is categorized into 5 phases namely framework of network, enrolment phase, D2D discovery phase, key production—authentication phase and content conveyance phase. Framework of network phase generates function parameters. Enrolment phase registers all user equipment (UE) for verification and also generate an appropriate user application code for respective UE. In this phase, HSS also manages a database that contains detail about all the enrolled. D2D discovery phase allows the UE to discover the neighbors under that proximity area. During the authentication phase, public as well as private secret keys are generated using Elliptic Curve Cryptography (ECC) and Elliptic Curve Diffie-Hellman (ECDH) algorithm. In addition to that, this phase implements hash based message authentication code (HMAC) to create application associated keys. In the last phase of content conveyance, most important step is to share Shared Secret Key (SSK) as it mainly responsible while decrypting original message. To make this transmission very secure, quantum channel is used. Quantum Cryptography plays a vital role in this phase for providing security to whole transmission process at high level. Now a days, advanced optical technologies are also using quantum cryptography to establish secured communication. The performance of the proposed SAP is evaluated and compared with the existing protocols by using multiple evaluation criteria such as cost of operation, computational overhead, storage overhead and energy consumption. This article also provides insights into various security threats such as MitM, replay attack, DoS attack, impersonation attack, known key attack due to use of ECC and ECDH. Also, SAP provides a strong pillar against eavesdropping attack due to quantum cryptography. Also, Bennett and Gilles Brassard (BB84) protocol linked with quantum electronics and physics, place a significant role for creation of quantum channel over classical channel, which took security of SAP at next level. [ABSTRACT FROM AUTHOR]

The article "Hybrid nanofabrication of AZ91D alloy-SiC-CNT and Optimize the drill machinability characteristics by ANOVA route" published in Optical & Quantum Electronics has been retracted due to concerns raised during an investigation. The retraction was based on issues such as the article being out of scope for the journal, inconsistencies in the peer-review process, and the use of inappropriate references or nonstandard phrases. While V. Mohanavel disagrees with the retraction, the Publisher was unable to contact some of the authors for their response. Springer Nature maintains neutrality in this matter. [Extracted from the article]

The article "Design of precoder for a MIMO-NOMA system using Gaussian mixture modelling" published in Optical & Quantum Electronics has been retracted by the Publisher due to concerns about compromised peer-review processes, inappropriate references, and being out of scope for the journal. The retraction was made after an investigation by the Publisher, who, in consultation with the Editors-in-Chief, no longer has confidence in the article's results and conclusions. One of the authors, S Markkandan, disagrees with the retraction, while the other authors have not responded to correspondence regarding this issue. [Extracted from the article]