Doklady Physics最新文献_第3页

Irreversible Einstein Gravity from Two-Sheet Null-Boundary Ledger Dynamics with Two Discriminator Tests 两页零边界分类帐动力学的不可逆爱因斯坦引力与两个判别器检验

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826600252

Daegene Song

{"title":"Irreversible Einstein Gravity from Two-Sheet Null-Boundary Ledger Dynamics with Two Discriminator Tests","authors":"Daegene Song","doi":"10.1134/S1028335826600252","DOIUrl":"10.1134/S1028335826600252","url":null,"abstract":"We present an irreversible completion of Einstein gravity as a controlled small-diamond approximation of a null-boundary ledger framework. The primitive input is protocol-level bookkeeping on a null screen patch: a context ((mathcal{A},omega )) fixing modular comparisons, a geometric capacity (mathcal{X}: = A{text{/}}(4{{G}_{{{text{ren}}}}})) in entropy units, and a nonnegative record ledger ({{N}_{{c}}}) counting logically irreversible register updates. A two-sheet carrier separates, within each update, the reference structure used to define increments from the record-bearing structure stabilized across updates, avoiding self-referential metric-increment ambiguities. Coarse-grained balance, together with the standard small-diamond modular-universality and covariant phase-space inputs, yields a local non-equilibrium screen law whose reversible sector recovers the Einstein equation. We clarify how ledger–CTP differs structurally from standard Schwinger–Keldysh, modified gravity, and stochastic gravity. We then propose two discriminator-style tests that directly target the ledger–CTP identification of record production with an irreducible imaginary influence phase: a gravitational Loschmidt-echo bound in atom interferometry and, within a stated linear/Gaussian completion class, a dissipation–noise consistency constraint linking any inferred non-GR propagation kernel to a correlated stochastic component in gravitational-wave data.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 5","pages":"129 - 137"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of Indium Concentration and Polarization-Graded Back Barriers in InAlN/GaN/AlGaN HEMTs 铟浓度和极化梯度后势垒对InAlN/GaN/AlGaN hemt的影响

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S102833582660015X

P. Gowtham, T. Subhashini, Rohith Bala Jaswanth B, R. S. Venkatesan

{"title":"Impact of Indium Concentration and Polarization-Graded Back Barriers in InAlN/GaN/AlGaN HEMTs","authors":"P. Gowtham, T. Subhashini, Rohith Bala Jaswanth B, R. S. Venkatesan","doi":"10.1134/S102833582660015X","DOIUrl":"10.1134/S102833582660015X","url":null,"abstract":"The impact of polarization-graded AlGaN back-barrier engineering on the DC and RF performance of InAlN/GaN HEMTs is systematically investigated. The study also investigates the influence of varying indium mole fraction (x) in the InxAl1 – xN barrier layer (x = 0.75–0.83). Compared to a uniform back-barrier structure, the graded back-barrier device demonstrates enhanced DC characteristics, delivering a higher drain current density of 0.73 A/mm vs. 0.66 A/mm at VGS = –3 V and VDS = 2 V. The graded structure also exhibits an improved peak transconductance of 0.61 S/mm, representing an 10% enhancement over the 0.56 S/mm achieved by the uniform back-barrier HEMT. Owing to reduced parasitic capacitances, the gate–source capacitance decreases from ≈1.80 × 10–12 to ≈1.75 × 10–12 F/mm, while the gate–drain capacitance is lowered from ≈5.35 × 10–13 to ≈5.0 × 10–13 F/mm. These improvements directly translate into superior RF performance, with the graded back-barrier device achieving a peak cutoff frequency of 54 GHz, compared to 50 GHz for the uniform back-barrier device. Furthermore, breakdown voltage is enhanced from ≈880 to ≈960 V, indicating improved electric-field management and carrier confinement.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 5","pages":"156 - 166"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Sustainable Jojoba-Oil Route for Nickel Oxide Nanograins: Preparation, Structure, and Dielectric Behavior 氧化镍纳米颗粒的可持续荷荷巴油路线：制备、结构和介电行为

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826600215

Ali H. Bashal

{"title":"A Sustainable Jojoba-Oil Route for Nickel Oxide Nanograins: Preparation, Structure, and Dielectric Behavior","authors":"Ali H. Bashal","doi":"10.1134/S1028335826600215","DOIUrl":"10.1134/S1028335826600215","url":null,"abstract":"Nickel oxide (NiO) nanograins were successfully synthesized through a green, eco-friendly route using jojoba oil as a natural precursor. This sustainable approach enables the formation of nanocrystalline NiO without relying on harsh chemicals or toxic solvents. XRD analysis confirmed the development of phase-pure NiO with characteristic reflections indexed to the (111), (200), (220), (311), and (222) planes of the C12/m1 space group, while a minor Ni(OH)2 phase was also detected. The average crystallite size, calculated from the Scherrer equation, was approximately 50 nm. SEM images revealed well-defined grains and clear grain boundaries, highlighting the polycrystalline nature of the product, whereas EDX spectra verified the presence of Ni and O along with trace elements such as Na, Cl, and C originating from the natural synthesis medium. Although electrical and dielectric measurements were conducted to probe charge-transport behavior, the primary significance of this work lies in demonstrating jojoba oil as an effective, sustainable, and low-impact precursor for producing high-quality NiO nanograins. This green synthesis pathway offers a promising alternative for the environmentally responsible fabrication of functional metal oxide nanomaterials.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 5","pages":"138 - 144"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Geometry-Induced Topological Superconductivity and Majorana Zero Modes in Carbon Nanotubes 碳纳米管中几何诱导的拓扑超导性和Majorana零模式

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826600136

Ismael Elias Erazo Velasco, Gabriela Carolina Miranda Villagomez, Mario Lizandro Franco Andrades

{"title":"Geometry-Induced Topological Superconductivity and Majorana Zero Modes in Carbon Nanotubes","authors":"Ismael Elias Erazo Velasco, Gabriela Carolina Miranda Villagomez, Mario Lizandro Franco Andrades","doi":"10.1134/S1028335826600136","DOIUrl":"10.1134/S1028335826600136","url":null,"abstract":"The mechanisms responsible for generation of Majorana zero modes in carbon nanotubes proximately represented by an s-wave superconductor and placed in a uniform axial magnetic field are theoretically and numerically analyzed. An effective 1D low-energy model is built on the basis of the Dirac description of electronic states of graphene taking into account the rolled-up structure geometry. It is shown that the quantization of transverse motion, the orbital contribution of a magnetic field (the Aharonov–Bohm effect), and the curvature-induced spin–orbit coupling jointly form a topologically nontrivial superconducting state. In the appropriate parametric mode, the effective Hamiltonian is reduced to a known 1D model with all its parameters expressed directly through the geometric characteristics of a nanotube and the value of an external magnetic field, without introducing phenomenological assumptions. The Majorana modes emerging at the nanotube edges are nonlocal quantum states protected by the superconducting gap, which makes them promising for implementing topological qubits. The analytical results are confirmed by the numerical simulation within the Bogoliubov–de Gennes Hamiltonian, which demonstrates the energy gap closing and reopening and the emergence of localized edge states.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 5","pages":"145 - 155"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the Possibilities of Using Bidirectional Long Short-Term Memory for Predicting Heavy-Metal Transport with Bottom Sediments of the Terek River 利用双向长短期记忆预测特雷克河底泥重金属运移的可能性

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826700035

M. V. Ivanov, I. O. Sinev, M. V. Kondratyeva, O. A. Ivanova, A. S. Kozodaev, M. S. Vinogradov

{"title":"On the Possibilities of Using Bidirectional Long Short-Term Memory for Predicting Heavy-Metal Transport with Bottom Sediments of the Terek River","authors":"M. V. Ivanov, I. O. Sinev, M. V. Kondratyeva, O. A. Ivanova, A. S. Kozodaev, M. S. Vinogradov","doi":"10.1134/S1028335826700035","DOIUrl":"10.1134/S1028335826700035","url":null,"abstract":"The rivers of the North Caucasus, particularly the Terek, experience significant anthropogenic loads of heavy metals (Pb, Cd, Zn), which accumulate in bottom sediments and, during flood periods, pose a risk of secondary pollution of floodplain agricultural lands. This paper presents a comparative analysis of the hydrological and sedimentological characteristics of the Terek and Yangtze rivers (Hunan Province, China). It is shown that both rivers exhibit similarities in three key parameters: a pronounced summer flood regime, the dominant role of fine suspended solids in pollutant transport, and the presence of anthropogenic sources of heavy metals (mining activities, industrial discharges). Based on the established similarities, the feasibility of adapting hybrid architectures with bidirectional long short-term memory networks and preliminary signal decomposition, which have been successfully tested on the Yangtze River, to predict Pb, Cd, and Zn concentrations in the Terek River was substantiated. The results of the study provide a scientific and methodological basis for subsequent calibration and verification of the model using our own field data, which it is planned to collect in 2026.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 4","pages":"99 - 106"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148459181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improved Electrostatic Performance of Hetero Oxide and Work-function Modulated Ferro Tunnel Field Effect Transistor for Low Power Applications 用于低功耗应用的改进的杂氧化物和工作功能调制铁隧道场效应晶体管的静电性能

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826600318

Vedvrat, Rajeev Kumar Sachan, Sushroot

{"title":"Improved Electrostatic Performance of Hetero Oxide and Work-function Modulated Ferro Tunnel Field Effect Transistor for Low Power Applications","authors":"Vedvrat, Rajeev Kumar Sachan,  Sushroot","doi":"10.1134/S1028335826600318","DOIUrl":"10.1134/S1028335826600318","url":null,"abstract":"The present work suggests and examines a hetero-oxide, dual-metal, negative-capacitance, double-gate tunnel field-effect transistor (HDM-NC-DGTFET) to achieve improved electrostatic control, ON-state current, and analog/RF characteristics to low-power applications. The suggested architecture combines (i) dual metal gate work-function engineering (φ1 < φ2), (ii) hetero-gate dielectric arrangement, and (iii) a ferroelectric covering to produce negative capacitance voltage amplification. The low-work-function gate at the source-channel interface not only sharpens the band bending and increases band-to-band tunneling (BTBT) but also the high-work-function drain-side gate prevents ambipolar conduction by reinforcing the channel-drain barrier. Extensive 2D TCAD simulations with a non-local BTBT model show a great deal of improvement over the traditional single-metal HSM-NC-DGTFET. The proposed device is able to attain a 90% increase in ON-current, 42% decrease in threshold voltage, and a 38% decrease in subthreshold swing. Work-function modulation and optimized dielectric eliminate ambipolar leakage. Also, the device demonstrates greater analog/RF figures of merit, such as increased levels of transconductance (gm), greater transconductance generation factor (TGF), higher cut-off frequency (fT), and gain-bandwidth product (GBP). The synergistic combination of hetero-oxide engineering, dual metal work-function modulation and negative capacitance effect makes the HDM-NC-DGTFET a good candidate in next-generation low-power, high-frequency nanoelectronic applications.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 6","pages":"167 - 177"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Composition-Driven Structural and Thermo-Physical Evolution in In–Sb–Se Chalcogenide Glasses: A Theoretical Study in - sb - se硫系玻璃成分驱动结构和热物理演化的理论研究

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826600094

Diksha Sharma, Rita Sharma, Lakshay Dhiman

{"title":"Composition-Driven Structural and Thermo-Physical Evolution in In–Sb–Se Chalcogenide Glasses: A Theoretical Study","authors":"Diksha Sharma, Rita Sharma, Lakshay Dhiman","doi":"10.1134/S1028335826600094","DOIUrl":"10.1134/S1028335826600094","url":null,"abstract":"The present work investigates the influence of indium incorporation on the structural and thermo-physical characteristics of In–Sb–Se chalcogenide glass systems, InxSb30Se70 – x (x = 0–25), using a theoretical framework. A set of composition-dependent parameters including average coordination number, bond energy, network constraints, heat of atomization, deviation from stoichiometry, and lone-pair electron concentration were evaluated to understand the evolution of network connectivity and thermal stability. The results indicate that increasing indium content leads to enhanced network rigidity, as reflected by higher coordination numbers, increased bond strength, and reduced structural disorder. The decrease in lone-pair electrons and deviation from stoichiometry suggests improved cross-linking within the glassy network, contributing to enhanced thermal stability. In addition, a simple machine-learning-based regression model was employed as a supplementary validation tool to examine correlations between selected structural parameters and the glass transition temperature (Tg). The close agreement between theoretical predictions and regression-based estimates confirms the consistency and robustness of the adopted approach. The present study provides a systematic theoretical understanding of composition-driven trends in In–Sb–Se chalcogenide glasses and offers useful guidance for tailoring their thermo-physical properties.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 6","pages":"188 - 193"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tailored Synthesis and Detailed Characterization of Ni–Mg Co-doped CuO Nanostructures for Photocatalytic Degradation Efficiency Ni-Mg共掺杂CuO纳米结构的合成及光催化降解效率的详细表征

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826600367

Sonia Attaf, Fouzia Abbas, Ouassila Benzaoui, Bouchra Slimani, Rosalba Fittipaldi, Chourouk Namoune, Rabeh Bensaha

{"title":"Tailored Synthesis and Detailed Characterization of Ni–Mg Co-doped CuO Nanostructures for Photocatalytic Degradation Efficiency","authors":"Sonia Attaf, Fouzia Abbas, Ouassila Benzaoui, Bouchra Slimani, Rosalba Fittipaldi, Chourouk Namoune, Rabeh Bensaha","doi":"10.1134/S1028335826600367","DOIUrl":"10.1134/S1028335826600367","url":null,"abstract":"In this study, we synthesized and investigated the influence of dopant nature on copper oxide nanoparticles (NPs) for four compositions: undoped CuO, Ni-doped CuO (Cu0.95Ni0.05O), Mg-doped CuO (Cu0.95Mg0.05O), and (Ni,Mg) co-doped CuO (Cu0.90Ni0.05Mg0.05O), using the sol–gel method. Samples were characterized through various characterization techniques and by photocatalytic performance. X-ray diffraction (XRD) analysis confirmed single-phase monoclinic CuO structure. (Ni,Mg) co-doping significantly reduced the average crystallite size from 20.95 to 6.24 nm. Scanning electron microscopy (SEM) demonstrated that the incorporation of Ni and Mg affected the morphology of the CuO NPS. Fourier-transform infrared (FTIR) spectra confirm the formation of CuO NPs. Moreover, (Ni,Mg) co-doping generated a synergistic electronic effect, where Ni narrowed and Mg widened the band gap, yielding an optimized band structure, improved light absorption in both the visible and UV ranges. This tunability is advantageous for photocatalytic applications, as the broader spectral response improves light harvesting and, consequently, photocatalytic efficiency.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 6","pages":"178 - 187"},"PeriodicalIF":0.3,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nonlinear Second Harmonic Generation of q-Gaussian Laser Beam in Cold Quantum Plasma with Relativistic and Ponderomotive Forces 冷量子等离子体中q-高斯激光束的非线性二次谐波产生

IF 0.3 4区物理与天体物理

Doklady Physics Pub Date : 2026-07-17 DOI: 10.1134/S1028335826600057

Arnika Sharma, Anuj Vijay

引用次数: 0

A Novel Approach for Fabrication of Functional Carbon–Ceramic Composites with High Resistance to Gas Plasma Treatment 一种制备高抗气体等离子体处理功能碳-陶瓷复合材料的新方法

IF 0.5 4区物理与天体物理

Doklady Physics Pub Date : 2026-05-15 DOI: 10.1134/S1028335826600240

I. V. Sukmanov, O. A. Butusova, V. A. Pogodin, A. N. Astapov

{"title":"A Novel Approach for Fabrication of Functional Carbon–Ceramic Composites with High Resistance to Gas Plasma Treatment","authors":"I. V. Sukmanov, O. A. Butusova, V. A. Pogodin, A. N. Astapov","doi":"10.1134/S1028335826600240","DOIUrl":"10.1134/S1028335826600240","url":null,"abstract":"This work is aimed to develop a technology for fabrication of high-temperature carbon–ceramic composite materials. The approach includes the following processing stages: the fabrication of filled carbon-fiber blanks, their subsequent carbonization, high-temperature heat treatment, and pyrolytic compaction. A distinctive feature of the technology is the impregnation of particles of refractory component precursors into the interlayer space, that ensures in situ synthesis and subsequent sintering of the ceramic component of the matrix during the carbonization and high-temperature heat treatment stages. This approach has been successfully tested in the fabrication of carbon–ceramic composites in the Cf/C system—carbides and borides of transition metals of IV (Hf, Ti) and V (Nb) groups. The results of gas-dynamic tests of samples of the resulting composites under the influence of high-speed, high-enthalpy flows of oxidizing gases are presented. It is noted that the number of functional layers and their thickness allow to regulate the magnitude of the thermal load by changing the rate of oxidation, ablation and the duration of each mode.","PeriodicalId":533,"journal":{"name":"Doklady Physics","volume":"71 3","pages":"86 - 92"},"PeriodicalIF":0.5,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147938768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0