Physica E-low-dimensional Systems & Nanostructures最新文献

{"title":"Two-dimensional GaN of wurtzite、hexagonal and haeckelite (4|8) structure with multiple layers: A first principle DFT study on structural and optoelectronic properties","authors":"Yuting Dai ,&nbsp;Sihao Xia ,&nbsp;Hongkai Shi ,&nbsp;Yuyan Wang ,&nbsp;Xian Wu ,&nbsp;Yu Diao","doi":"10.1016/j.physe.2025.116193","DOIUrl":"10.1016/j.physe.2025.116193","url":null,"abstract":"<div><div>This study aims to investigate the optoelectronic properties of three different structures of two-dimensional GaN, namely wurtzite, hexagonal, and haeckelite, through first-principles calculations. The goal is to provide a theoretical foundation for the design and development of high-performance optoelectronic devices. As a new type of semiconductor material, two-dimensional GaN has attracted much attention due to its excellent optoelectronic properties. In our study, we found that as the layer thickness increases, the optimal structure of two-dimensional GaN transitions from the hexagonal phase to the haeckelite phase, and finally stabilizes in the wurtzite structure. During this process, the work function continuously increases and tends to stabilize, with the wurtzite structure's work function eventually stabilizing at 5.50 eV, while the work functions of the hexagonal and haeckelite (4|8) structures stabilize around 7.35 eV. The wurtzite structure exhibits a significantly enhanced internal electric field between layers, whereas the hexagonal and haeckelite structures do not show interlayer polarization due to the coincidence of positive and negative charge centers. Compared to bulk materials, two-dimensional GaN shows a larger bandgap, which gradually decreases with increasing layer thickness and tends to stabilize at around 10 layers. The hexagonal structure has the largest bandgap, while the wurtzite and haeckelite structures have relatively smaller bandgaps. Specifically, the bandgap of the wurtzite structure decreases from 5 eV for a single layer to approximately 1.50 eV at around 10 layers. The hexagonal structure exhibits the largest bandgap of 2.61 eV at 5 layers, stabilizing at around 2.60 eV at 10 layers. The haeckelite structure's bandgap decreases from 2.71 eV at 5 layers to 1.61 eV at 15 layers. The valence band maximum is primarily contributed by the p-states of nitrogen and gallium, while the conduction band minimum originates from the hybridization of the s-orbitals of nitrogen and gallium. Additionally, the effective mass continuously decreases with increasing layer thickness, with the haeckelite structure showing the highest effective mass of 0.97m₀ at a single layer, reducing to 0.27m₀ at 15 layers. Our research also examined the optical properties of these three structures, providing a comprehensive understanding of the optoelectronic performance of two-dimensional GaN. These findings not only reveal the relationship between the structure and properties of two-dimensional GaN but also offer important references for future applications in the field of solid-state optoelectronics.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"168 ","pages":"Article 116193"},"PeriodicalIF":2.9,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Investigating transition metal (Fe, Co, Ni)-doped biphenylene network as a sensor for SF6 decomposition molecules detection at the atomic scale","authors":"Jia-Yao Yuan ,&nbsp;Zhi-Gang Shao","doi":"10.1016/j.physe.2025.116178","DOIUrl":"10.1016/j.physe.2025.116178","url":null,"abstract":"<div><div>For the detection of SF₆ decomposition products, the development of high performance sensor materials is extremely critical. Biphenylene network (BPN), an emerging 2D carbon material, shows great potential in gas sensing. However, pristine BPN has limited performance in detecting SF₆ decomposition products, and doping strategies are required to optimize its sensing performance. The adsorption mechanism and gas-sensitive properties of three transition metal-doped biphenylene network (TM-BPN) on SF₆ decomposition products (SO₂ and H₂S) are investigated using first-principle calculations. After identifying the most stable doping sites, the correlation adsorption calculations show a significant charge transfer between TM-BPN and SO₂, accompanied by the formation of covalent bonds. Among them, the adsorption energy of Fe-BPN on SO₂ is −1.308 eV, which shows strong chemisorption. At the optimum operating temperature, the Fe-BPN system has a fast recovery time of 15.5 s, a high change of the work function of about 1 eV, and a strong resistivity change. So this gas-sensitive material is well suited for detecting SO₂ molecules. The computational results in this paper provide theoretical guidance for advancing the development of BPN as a high-sensitivity gas sensor for electrical insulation equipment.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"168 ","pages":"Article 116178"},"PeriodicalIF":2.9,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Tunable fano-like resonances in graphene metasurface for quad-frequency optoelectronic sensing","authors":"Mingfei Wang ,&nbsp;Wei Cui ,&nbsp;Yixuan Wang ,&nbsp;Mengyao Li ,&nbsp;Xin Qie","doi":"10.1016/j.physe.2025.116191","DOIUrl":"10.1016/j.physe.2025.116191","url":null,"abstract":"<div><div>To address the increasing demands in optoelectronic sensing technologies, we propose a novel patterned graphene-based metasurface with tunable electromagnetic properties, tailored for advanced sensing applications. Finite-Difference Time-Domain (FDTD) simulations are employed to design and analyze the metasurface under terahertz excitation, enabling the modulation of double and triple Fano-like resonances by adjusting structural parameters, Fermi levels, and carrier mobility. Bright-dark mode theory and electric field distribution analyses provide insights into the underlying resonance mechanisms. Furthermore, the metasurface demonstrates high sensitivity in cholesterol concentration detection, achieving a maximum sensitivity of 1.8424 THz/RIU and a figure of merit (FOM) of 44.27. Notably, the graphene metasurface supports quad-frequency sensing, showcasing its potential for precise environmental monitoring and tunable optoelectronic device applications.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"168 ","pages":"Article 116191"},"PeriodicalIF":2.9,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Valley-dependent electronic transport in a graphene with double magnetic-strained barriers","authors":"Man-Ting Li,&nbsp;Yang-Lai Hou,&nbsp;Jian-Duo Lu,&nbsp;Jin-Ze Ye,&nbsp;Jing Huang","doi":"10.1016/j.physe.2025.116176","DOIUrl":"10.1016/j.physe.2025.116176","url":null,"abstract":"<div><div>Using the transfer-matrix method, we investigate the valley-dependent electronic transport in a graphene with double magnetic-strained barriers. The effects of the magnitude, position and width of the strained barriers as well as the strength of the magnetic field on the electronic conductance and the valley polarization in the parallel (P) configuration are analyzed. In order to comprehensively understand and apply this model, we also study how the strength of the magnetic field and the magnitude of the strained barriers affect the valley polarization when the ferromagnetic metal (FM) stripes are shifted from P configuration to antiparallel (AP) configuration. The results show that the magnetic field and the strains significantly influence the electronic transport properties in both P and AP configurations. Therefore, this work provides crucial help for understanding valley-dependent transport characteristics, and the studied graphene nanostructure is useful for designing the valleytronic device.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"168 ","pages":"Article 116176"},"PeriodicalIF":2.9,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Thermoelectric properties of a correlated polar single molecular transistor in the presence of a magnetic field and dissipation","authors":"Pooja Saini ,&nbsp;Manasa Kalla ,&nbsp;Soma Mukhopadyay ,&nbsp;Ashok Chatterjee ,&nbsp;I. Yu Popov","doi":"10.1016/j.physe.2024.116175","DOIUrl":"10.1016/j.physe.2024.116175","url":null,"abstract":"<div><div>The spin Seebeck effect is investigated in a correlated polar single molecular transistor in the presence of dissipation and a magnetic field. The Anderson-Holstein-Caldeira-Leggett model is used to study the heat transport characteristics of the system. Assuming the phonons to be in the coherent state, the effective electronic Hamiltonian is solved using the Keldysh method. The spectral function, conductance, spin Seebeck effect, and spin-polarized current densities are calculated. As the magnetic field increases, the charge conductance splits into two symmetric peaks, while the spin conductance separates into two antisymmetric peaks. In the absence of a magnetic field, only the charge conductance and Seebeck coefficient are maximum, while the spin conductance and spin Seebeck coefficient remain zero. However, as the magnetic field increases, both spin conductance and spin Seebeck coefficient undergo an enhancement. We also observe a substantial enhancement in the thermopower with the increase in the electron-phonon coupling.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"168 ","pages":"Article 116175"},"PeriodicalIF":2.9,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143174170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Continuous tuning of band gap by strain engineering in new predicted 13H-Si allotrope","authors":"Teng Wan ,&nbsp;Qingyang Fan ,&nbsp;Dangli Gao ,&nbsp;Ruida Zhao ,&nbsp;Sining Yun","doi":"10.1016/j.physe.2025.116177","DOIUrl":"10.1016/j.physe.2025.116177","url":null,"abstract":"<div><div>Diamond silicon and most of its allotropes have indirect band gaps that do not allow electrons to propagate directly between the valence and conduction band edges due to momentum mismatch, limiting their performance and efficiency in optoelectronic devices. With the rapid development of the optoelectronic industry, searching for new silicon allotropes with adjustable and/or direct band gap has become increasingly urgent. Here, we predict five new silicon allotropes 13H-Si with continuously tunable band gap, high mechanical, dynamic and thermal stability under tensile strain. As expected, besides their adjustable band gaps in a wide range (0.80–1.30 eV), the indirect-to-direct band gap transition can be achieved in these predicted silicon allotrope 13H-Si under tensile strain (4.5–9.0 %) along <em>a-</em> and <em>b-</em>axis. Especially, these predicted 13H-Si not only demonstrate the stronger visible light absorption ability than diamond silicon, but also show the enhanced absorption intensity under axial strain. The current research not only enriches the types of silicon allotropes, but also accumulates data for the application of silicon materials in the field of solar photovoltaics.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"168 ","pages":"Article 116177"},"PeriodicalIF":2.9,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143173291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Electrical contact between 2D material NbS2 and WSSe","authors":"Jingjun Chen,&nbsp;Zelong Ma,&nbsp;Danni Wang,&nbsp;Xu Li,&nbsp;Songyang Li,&nbsp;Baoan Bian","doi":"10.1016/j.physe.2025.116179","DOIUrl":"10.1016/j.physe.2025.116179","url":null,"abstract":"<div><div>Achieving Ohmic contact at the metal-semiconductor interface is a key technological issue for miniaturization and high performance of nanoelectronic devices. In this study, we design a metal-semiconductor heterostructure consisting of cold metal NbS₂ and semiconductor WSSe, and study the properties of the electric contact by first-principles calculations. SWSe/NbS₂ and SeWS/NbS₂ both show p-type Schottky contact with different Schottky barrier heights and high charge injection efficiency. The heterojunctions can achieve the Ohmic contacts under the modulation of the interlayer distance, strain and electric field. In addition, the electric field causes changed contact type from p-type Schottky contact to n-type Schottky contact for both heterojunctions. Different interface contact for WSSe/NbS₂ induces different electronic properties. The results provide the theoretical guidance for the application of WSSe/NbS₂ heterojunction in the development of next-generation electronic and optoelectronic devices.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"168 ","pages":"Article 116179"},"PeriodicalIF":2.9,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143173292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Impact of strain and electron–phonon coupling on thermoelectric performance of Germanene","authors":"Neelesh Gupta ,&nbsp;Anup Shrivastava ,&nbsp;Jost Adam","doi":"10.1016/j.physe.2024.116150","DOIUrl":"10.1016/j.physe.2024.116150","url":null,"abstract":"<div><div>This manuscript describes the thermoelectric properties of monolayer germanene under the influence of biaxial strain using the combined approach of ab initio and semi-classical Boltzmann transport theory. To achieve excellent precision in the estimation of the thermoelectric behavior of strained germanene, the research delves into the temperature-dependent scattering time, particularly emphasizing the electron–phonon coupling effect. Incorporating both optical and acoustic phonons is always crucial and key for precisely estimating the scattering time, surpassing the limitations of the deformation potential approximation method. By examining the impact of strain on monolayer germanene and accounting for its scattering time, this approach provides a more practical means of gauging the thermoelectric performance of germanene under the presence of bi-axial strain. Moreover, the study extends its analysis to doped germanene with bi-axial strain, employing the rigid band approximation to investigate its thermoelectric performance. The research extensively estimates the transport properties for both intrinsic and extrinsic germanene, utilizing the hybrid functional HSE06. Additionally, the lattice thermal conductivity of germanene is estimated and compared for the strained and unstrained conditions. The analysis of thermal conductivity involves considering the effects of group velocity and phonon scattering time, providing insights into the nature of heat transport in strained germanene systems. Overall, this comprehensive study contributes to a deeper understanding of the thermoelectric properties of germanene under strain and lays the foundations for potential applications in electronic and thermal devices.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"167 ","pages":"Article 116150"},"PeriodicalIF":2.9,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Probing the magnitude of Rashba spin–orbit coupling in a double quantum dot system via finite-frequency shot noise","authors":"Hai-Bin Xue,&nbsp;Xiao-Yan Ma,&nbsp;Bin Chen,&nbsp;Jian-Bin Chen,&nbsp;Li-Li Xing","doi":"10.1016/j.physe.2024.116159","DOIUrl":"10.1016/j.physe.2024.116159","url":null,"abstract":"<div><div>In the coupled quantum dot (QD) system, the electrical manipulation of spin degree of freedom of electron based on the spin–orbit coupling (SOC) is one of the important research fields for QD-based spintronic devices. Consequently, how to quantitatively extract the magnitude of the SOC of the coupled QD system is an important issue. Here, we study the finite-frequency shot noise of electron transport through a serially coupled double QD system with Rashba SOC. It is demonstrated that the existence of peaks and dips of the finite-frequency shot noise originates from the quantum coherence of the serially coupled double QD system, and the positions of the peaks and dips are determined by the differences between the energy eigenvalues of the coherent singly-occupied eigenstates that forming the off-diagonal elements of the reduced density matrix. In particular, when the degeneracy of the differences between the energy eigenvalues of the coherent singly-occupied eigenstates equals one, the finite-frequency shot noise shows a peak, whereas the degeneracy equals two, the finite-frequency shot noise shows a dip. Moreover, the spin polarization of the electrodes and the QD-electrode coupling strength have almost no influence on the positions of the peaks and dips, but have some influences on the width and values of peaks and dips. Therefore, the magnitude of the Rashba SOC and the spin-conservation hopping strength can be quantitatively determined by the positions of peaks and dips of the finite-frequency shot noise.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"167 ","pages":"Article 116159"},"PeriodicalIF":2.9,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Formation of vanadium dioxide nanocrystal arrays via post-growth annealing for stable and energy-efficient switches","authors":"K.E. Kapoguzov ,&nbsp;S.V. Mutilin ,&nbsp;N.I. Lysenko ,&nbsp;V.N. Kichay ,&nbsp;L.V. Yakovkina ,&nbsp;B.V. Voloshin ,&nbsp;V.A. Seleznev","doi":"10.1016/j.physe.2024.116165","DOIUrl":"10.1016/j.physe.2024.116165","url":null,"abstract":"<div><div>The abrupt and reversible semiconductor-metal phase transition in vanadium dioxide nanocrystals has attracted considerable attention for potential applications in oxide electronics, including neuromorphic systems. This study presents a systematic investigation of post-growth annealing conditions for the formation of single VO₂ M-phase nanocrystals arrays from VO_x films synthesized by atomic layer deposition. The composition of the initial VO_x films and the annealing parameters were found to significantly affect the morphology, phase composition and electrical properties of the obtained single nanocrystal arrays. Our results demonstrate that the formation of VO₂ M-phase nanocrystal arrays occurs at annealing temperatures of 650 °C and above, irrespective of the initial film composition. More homogeneous in size nanocrystals are formed from initial VO_x films with higher V⁺⁴ content. The structures with the initial V⁺⁴ content of 60 % annealed at 650 °C for 2 h demonstrates the resistive switching with an energy less than 150 fJ, and a total number of stable switching cycles more than 10¹⁰. Our results pave the way for the novel energy-efficient nanoelectronic and nanophotonic devices based on VO₂ nanoparticles.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"167 ","pages":"Article 116165"},"PeriodicalIF":2.9,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}