{"title":"Applied electric and magnetic field effects on the bandgap formation and antiferromagnetic ordering in AA-stacked Bilayer Graphene","authors":"V. Apinyan, T. Kopeć","doi":"10.1016/j.physe.2025.116235","DOIUrl":"10.1016/j.physe.2025.116235","url":null,"abstract":"<div><div>In this study, we consider a two-layer graphene structure stacked in the AA form and exposed to the influence of two different electric fields applied to different layers. The graphene layers are also subjected to an external magnetic field perpendicular to the planes of the layers. We investigate the possible effects of the applied in-plane fields and the magnetic field on excitonic pairing, antiferromagnetic order, and the chemical potential. Simultaneously, we analyze the effects of the interlayer Coulomb interaction potential on the physical properties of the considered system. We demonstrate that the application of planar electric fields leads to the formation of an unusually large bandgap in the electronic band structure, which is not typical for AA-stacked bilayer graphene. We discuss various values of the applied electric field potentials and show their influence on the electronic band structure of the system. Additionally, we identify the existence of a critical value of the magnetic field above which Wigner crystallization-like effect is present for the electrons, also affecting the excitonic gap in one spin channel. The results obtained in this study could be important for applications of AA-stacked bilayer graphene as a large band-gap material.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"171 ","pages":"Article 116235"},"PeriodicalIF":2.9,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684135","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}
Jun-Jie Yuan , Cui Jiang , Tong Gong , Lian-Lian Zhang , Wei-Jiang Gong
{"title":"Bound state in continuum and its superconducting-induced modification in the two-channel Fano–Anderson structure","authors":"Jun-Jie Yuan , Cui Jiang , Tong Gong , Lian-Lian Zhang , Wei-Jiang Gong","doi":"10.1016/j.physe.2025.116231","DOIUrl":"10.1016/j.physe.2025.116231","url":null,"abstract":"<div><div>This work systematically investigates the electronic transport properties of multi-quantum-dot (multi-QD) systems in a two-channel Fano–Anderson structure using non-equilibrium Green’s function method. It is found that the coupling asymmetry between QDs and leads, QD levels, and external magnetic flux are key factors to induce rich quantum transport phenomena, including bound states in continuum (BIC) and the Fano antiresonance. By regulating the number and spatial symmetry of QDs, effective control of these quantum effects can be achieved, exhibiting clear odd–even oscillation patterns. In the presence of superconducting proximity effect, the Andreev reflection can also contribute to the electron transport properties, but the BIC phenomena tend to be more notable. These results help to understand the transport characteristics of the two-channel Fano–Anderson structure.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"171 ","pages":"Article 116231"},"PeriodicalIF":2.9,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636744","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}
Agustin Matias Mancardo Viotti , Edgar Alejandro Bea , Alejandro Gabriel Monastra , María Florencia Carusela
{"title":"Thermal transport across a vacuum gap between two reconstructed Si-nanomembranes","authors":"Agustin Matias Mancardo Viotti , Edgar Alejandro Bea , Alejandro Gabriel Monastra , María Florencia Carusela","doi":"10.1016/j.physe.2025.116232","DOIUrl":"10.1016/j.physe.2025.116232","url":null,"abstract":"<div><div>In this work we examine the interaction energy between two reconstructed silicon nanomembranes using a density-functional-based tight-binding (DFTB) approach, focusing on its impact on thermal conductance across a nanogap. By coupling the DFTB method with a harmonic atomistic model, we calculate the vibrational modes (phonons) and the equilibration times, which are directly related to the thermal conductance. Our findings show that surface reconstruction and the relative alignment of facing dimer structures significantly influence the phononic contribution to thermal conductance. Although the harmonic model simplifies the interactions of the real system,our results agree well with previous studies, demonstrating that this model captures key aspects of phonon-mediated heat transfer. Overall, our approach provides a computationally efficient method for understanding phononic heat transfer across nanogaps, with implications for designing nanoscale thermal management systems.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"171 ","pages":"Article 116232"},"PeriodicalIF":2.9,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684136","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":"First-principles study on 2D ferromagnetic semiconductor in Janus single-layer CrXY (X = P, As; Y = Cl, Br, I)","authors":"Xiaoli Jin, Wenhui Wan, Busheng Wang, Yong Liu","doi":"10.1016/j.physe.2025.116230","DOIUrl":"10.1016/j.physe.2025.116230","url":null,"abstract":"<div><div>Two-dimensional materials possessing both magnetic and semiconducting properties are desirable for spintronic applications. Inspired by the synthesis of Janus MoSSe, we predicted that Janus single-layer CrXY (X <span><math><mo>=</mo></math></span> P, As; Y <span><math><mo>=</mo></math></span> Cl, Br, I) is an intrinsic ferromagnetic semiconductor with an indirect band gap using first-principles calculations. CrPCl and CrPBr exhibit an easy magnetization plane while other single layers have an easy axis, due to the opposite contribution from the Cr ion and nonmetallic atoms. The magnetic anisotropic energy (MAE) of single-layer CrXY is <span><math><mrow><mn>61</mn><mo>−</mo><mn>673</mn></mrow></math></span> <span><math><mrow><mi>μ</mi><mi>eV</mi></mrow></math></span>. Single-layer CrXY has a high critical temperature (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>) of <span><math><mrow><mn>743</mn><mo>−</mo><mn>1166</mn></mrow></math></span> K for the Berezinskii–Kosterlitz–Thouless transition or the paramagnetic-to-ferromagnetic phase transition. Biaxial strains affect the band gap, MAE, and <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> of single-layer CrXY. Tensile strains raise the <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> by weakening the anti-ferromagnetic direct exchange interaction, while compressive strains reduce the band gap and enhance the MAE. The high <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> and controllable magnetic properties make Janus single-layer CrXY (X <span><math><mo>=</mo></math></span> P, As; Y <span><math><mo>=</mo></math></span> Cl, Br, I) hold promise for spintronic applications.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116230"},"PeriodicalIF":2.9,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620851","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}
Weiran Hu , Shuochen Yang , Jiangfeng Tian , Zirong He , Liang Qiu , Fangxin Zhang
{"title":"The performance of quantum battery in a common dephasing environment","authors":"Weiran Hu , Shuochen Yang , Jiangfeng Tian , Zirong He , Liang Qiu , Fangxin Zhang","doi":"10.1016/j.physe.2025.116229","DOIUrl":"10.1016/j.physe.2025.116229","url":null,"abstract":"<div><div>The quantum battery’s performance under the influence of a common environment is investigated. The battery and charger interact with each other, and have symmetrically or asymmetrically dephasing coupling with the environment. For the symmetrical coupling, the stored energy can be totally extracted and the conversion efficiency could reach the maximum value 1. The stored energy, ergotropy and conversion efficiency will reach their peak values more quickly with the increasing of the asymmetrical coupling at the price of the decreasing of the peak values. It is also found that the effect of the battery-charger interaction on the dephasing could be used to improve the performance of quantum battery. Furthermore, quantum battery’s performance is negatively correlated with coherence of the battery-charger system.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116229"},"PeriodicalIF":2.9,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620753","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":"Shape and size effects on electronic thermodynamics in nanoscopic quantum dots","authors":"J.A. Gil-Corrales , C.A. Dagua-Conda , M.E. Mora-Ramos , A.L. Morales , C.A. Duque","doi":"10.1016/j.physe.2025.116228","DOIUrl":"10.1016/j.physe.2025.116228","url":null,"abstract":"<div><div>The thermodynamic properties of strongly confined semiconductor nanostructures are significantly influenced by their geometry because the thermal de Broglie wavelength of the particles is comparable to the size of the structure. GaAs quantum dots (QDs) are nanostructures that can be configured in various geometrical forms, which makes them excellent candidates for studying how geometrical variations affect their thermodynamic properties. In this work, we present the study of the thermodynamic properties of a GaAs QD in spherical, cylindrical, cubic, and pyramidal shapes, through the finite element method (FEM) considering external infinite confinement and the effective mass approximation. The design of QDs guarantees the same volume (V) and cross-sectional area (A) for each case, providing structures with similar size characteristics. We observe stepwise behaviors in the particle number and entropy as a function of chemical potential due to shape dependence for the highest confinement configuration, which agrees with the nature of the Fermi–Dirac distribution function. Finally, we present the effect of geometrical shape for all geometrical configurations of the QD. We compare the thermodynamic properties of each arrangement and investigate the heat capacity response for different temperatures.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116228"},"PeriodicalIF":2.9,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143620752","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}
Rachid El Aitouni , Ahmed Jellal , Pablo Díaz , David Laroze
{"title":"Laser-assisted tunneling and Hartman effect in graphene under scalar potential and exchange fields","authors":"Rachid El Aitouni , Ahmed Jellal , Pablo Díaz , David Laroze","doi":"10.1016/j.physe.2025.116227","DOIUrl":"10.1016/j.physe.2025.116227","url":null,"abstract":"<div><div>We study the tunneling effect of Dirac fermions in a graphene sheet by introducing a potential barrier in a region of width <span><math><mi>D</mi></math></span> exposed to laser field. This sheet is placed on a boron nitride/ferromagnetic substrate such as cobalt or nickel. By using the Floquet theory, we determine the solutions of the energy spectrum. We calculate the transmission and reflection coefficients by applying the boundary conditions along with the transfer matrix method. These coefficients help determine their probabilities by current densities and group delay times by their phases. We numerically show that the laser field plays a crucial role in this structure, as it completely suppresses Klein tunneling compared to the case without laser. Furthermore, in contrast to the Hartman effect, the group delay time becomes dependent on the barrier width with the appearance of additional peaks. This suggests that fermion-field interactions cause additional delays within the barrier and also help to reduce spin coupling. Adding BN layers increases the interval of transmission suppression and completely eliminates coupling after the addition of three BN layers. Total reflection is observed for incident fermions with an angle less than <span><math><mrow><mo>−</mo><mn>1</mn></mrow></math></span> or greater than one.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116227"},"PeriodicalIF":2.9,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610809","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":"Existence of Mexican-hat dispersion and symmetry group of a layer","authors":"Vladimir Damljanović","doi":"10.1016/j.physe.2025.116224","DOIUrl":"10.1016/j.physe.2025.116224","url":null,"abstract":"<div><div>Increased interest in physics of graphene and other two-dimensional materials boosted investigations of band structure near nodal points and lines. In contrast, group theoretical explanation of simple bands (that do not touch other bands), is sporadically present in the literature. This paper presents electronic dispersions up to fourth order in momentum, near Brillouin zone (BZ) high symmetry points of all eighty layer groups. The method applies to non magnetic materials both with or without spin–orbit coupling. Particular attention is devoted to Mexican-hat dispersion, showing that it can appear only at BZ center of hexagonal layer groups. Presented symmetry adapted Taylor expansion of bands can be used to fit ab-initio or experimental band structures, or for analytical calculation of crystal properties. The results presented here might serve also as a guiding tool for design of new two-dimensional materials.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116224"},"PeriodicalIF":2.9,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610808","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":"Effect of the position of a hydrogen-like impurity on the generation of the third harmonic in a cylindrical quantum dot","authors":"A.A. Portacio , D. Madrid , D.A. Rasero","doi":"10.1016/j.physe.2025.116223","DOIUrl":"10.1016/j.physe.2025.116223","url":null,"abstract":"<div><div>This paper presents a theoretical study of the third-order nonlinear optical susceptibility in a GaAs/Ga<sub>0.6</sub>Al<sub>0.4</sub>As cylindrical quantum dot (CDQ) with a hydrogen-like impurity inside. The variational method was utilized to calculate the energies and wave functions corresponding to the bound states of the impurity, which include the <span><math><mrow><mn>1</mn><mi>s</mi></mrow></math></span>-like, <span><math><mrow><mn>2</mn><msub><mrow><mi>p</mi></mrow><mrow><mo>−</mo></mrow></msub></mrow></math></span>-like, <span><math><mrow><mn>2</mn><msub><mrow><mi>p</mi></mrow><mrow><mo>+</mo></mrow></msub></mrow></math></span>-like, and <span><math><mrow><mn>2</mn><msub><mrow><mi>p</mi></mrow><mrow><mi>z</mi></mrow></msub></mrow></math></span>-like states, with consideration of the impurity’s motion within the cylindrical quantum dot. The findings indicate that the resonant peaks of the optical third harmonic generation (THG) coefficient undergo a red shift as the impurity is displaced from the center of the CDQ towards the potential barrier. This shift can be attributed to a reduction in the average electrostatic interaction between the impurity and the surrounding ion as the impurity approaches the potential barrier. This phenomenon can be attributed to the decreased electrostatic attraction between the impurity and the quantum dot core as the impurity moves away from the center and approaches the region of higher potential confinement. These findings have significant implications for the design and optimization of quantum dot-based optoelectronic devices, as manipulation of the impurity position can provide additional control over the nonlinear optical properties of these systems.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116223"},"PeriodicalIF":2.9,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143593302","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}
Jiawei Shen , Qingxiao Zhou , Xinglong Yan , Weiran Li , Weiwei Ju , Chengyou Cai
{"title":"4d and 5d transition-metal doped Janus PtSSe as a viable sensitive sensor toward COCl2","authors":"Jiawei Shen , Qingxiao Zhou , Xinglong Yan , Weiran Li , Weiwei Ju , Chengyou Cai","doi":"10.1016/j.physe.2025.116234","DOIUrl":"10.1016/j.physe.2025.116234","url":null,"abstract":"<div><div>The adsorption behaviors, electronic and gas-sensing properties of phosgene (COCl<sub>2</sub>) on perfect, defected (S- and Se-vacancy), and transition-metal doped (TMs: Pd, Hf, Ta, W, Re, Os, Ir, and Au) PtSSe monolayer were explored by density functional theory (DFT). Pristine PtSSe monolayer exhibited long adsorption distance, small adsorption energy and low charge transfer for phosgene with physical adsorption. Constructing S- and Se-vacancy enhanced the PtSSe's sensitivity to phosgene, while it remained as physical adsorption nature. Furthermore, the adsorption stability of PtSSe toward COCl<sub>2</sub> was further improved after the introduction of Pd, Hf, Ta, W, Re, Ir dopants. The large adsorption energies and high charge transfer suggested that the adsorption mechanism of COCl<sub>2</sub> was converted to chemical adsorption. Moreover, the large gas response and suitable recovery time indicated the Re-doped Janus PtSSe monolayer could be reusable gas sensors for COCl<sub>2</sub> detection with high sensitivity at room temperature. These results offer insights into the design of gas sensors capable of detecting the highly toxic COCl<sub>2</sub> gas.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116234"},"PeriodicalIF":2.9,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143577349","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}