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

{"title":"High-performance photodetector based on hybrid 2D WSe2/Ag-in-Ga-S QDs heterojunction","authors":"Jiahao Yang,&nbsp;Banqin Ruan,&nbsp;Zhentao Ke,&nbsp;Jiahao Zhang,&nbsp;Yiyang An,&nbsp;Zixuan Guo,&nbsp;Zhi Li,&nbsp;Xiufeng Song,&nbsp;Haibo Zeng","doi":"10.1016/j.physe.2025.116391","DOIUrl":"10.1016/j.physe.2025.116391","url":null,"abstract":"<div><div>Two-dimensional (2D) materials have emerged as a prominent research focus due to their excellent properties and broad application. Among these, tungsten diselenide (WSe₂), a representative transition-metal dichalcogenide (TMDC), exhibits high carrier mobility and a tunable band gap when reduced to a 2D structure, making it particularly attractive for electronic and optoelectronic applications. However, the inherent weak absorption in 2D materials remains a fundamental limitation. To address this challenge, we developed a heterojunction photodetector by integrating Ag-In-Ga-S (AIGS) quantum dots (QDs) with 2D WSe₂. The device combines the superior high carrier mobility of 2D materials with the strong light-harvesting capability of quantum dots, facilitating efficient photogenerated carrier separation and enhanced photocurrents, thereby improving photoresponse performance. The obtained heterojunction demonstrates extraordinary optoelectronic performance, achieving a responsivity of 1.81 × 10⁴ A/W, a detectivity of 1.3 × 10¹³ Jones and an external quantum efficiency of 4.27 × 10⁵ %. These results indicate the significant potential of 2D materials/QDs hybrid systems for advanced photodetector applications.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116391"},"PeriodicalIF":2.9,"publicationDate":"2025-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145324745","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":"Two-dimensional high-temperature magnetic MoNX2 (X = F, Cl, Br, I) with piezoelectricity, ferroelectricity, and optical anisotropy","authors":"Wen-Zhi Xiao,&nbsp;Gang Xiao,&nbsp;Hai-Qing Xu,&nbsp;Xin-Hua Gao,&nbsp;Jun He","doi":"10.1016/j.physe.2025.116389","DOIUrl":"10.1016/j.physe.2025.116389","url":null,"abstract":"<div><div>Two-dimensional (2D) multifunctional materials with distinctive features such as magnetic, ferroelectric, piezoelectric, and optical property are in high demand due to their potential applications in novel nanoscale devices. Herein, based on first-principles calculations, we present a family of 2D multiferroic MoNX₂ (X = F, Cl, Br, I) materials. Among them, MoNF₂ is an anti-ferroelectric (AFE) ferromagnetic (FM) semiconductor with Curie temperature (T_C) of 497 K. MoNX₂ (X = Cl, Br) are ferroelectric (FE) antiferromagnetic (AFM) semiconductors. All of them exhibit an in-plane spontaneous electric polarization of up to 260 pC m⁻¹ and piezoelectric response. The FE switching energy barrier is no more than 0.1 eV per atom for them. Additionally, they exhibit strong linear optical dichroism and hyperbolicity in the visible light region. The alignments of the band edges of MoNX₂ (X = Cl, Br, I) with the redox potentials of water show that these materials are suitable for use as photocatalysts for water splitting. Their intriguing magnetic, electronic, ferroelectric, piezoelectric and optical properties render them ideal for use in high-performance, multifunctional applications.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116389"},"PeriodicalIF":2.9,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145324744","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":"Manipulation of valley polarization and anomalous valley Hall effect in monolayer ferrovalley AgMoP2S6","authors":"Lan Luo ,&nbsp;Xianjuan He ,&nbsp;Wenzhe Zhou ,&nbsp;Qinglin Xia ,&nbsp;Fangping Ouyang","doi":"10.1016/j.physe.2025.116387","DOIUrl":"10.1016/j.physe.2025.116387","url":null,"abstract":"<div><div>Due to the role of the valley as an information carriers, two-dimensional valleytronics materials have broad prospects in information storage in the future. However, materials with intrinsic valley polarization are rare. In our work, using first-principles calculations, we propose a valleytronics material monolayer (ML) AgMoP₂S₆ with a ferromagnetic(FM) ground state. The ferromagnetic exchange interaction breaks the time-reversal symmetry, which results in a spontaneous valley polarization of 78 meV at the K/-K points on the valence band under the action of strong SOC. The valley polarization can be tuned by biaxial strain and Hubbard U, and when the tensile strain exceeds 4 % and U exceeds 2 eV, valley polarization also appears in the conduction band. Under the action of an in-plane electric field, the breaking of valley degeneracy makes the appearance of anomalous valley Hall effect (AVHE) effect a possibility. ML AgMoP₂S₆ is an ideal valleytronics material.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116387"},"PeriodicalIF":2.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267669","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":"Anomalous Seebeck effect in non-Hermitian double quantum dots","authors":"Pengbin Niu ,&nbsp;Li Xu ,&nbsp;Hui Yao ,&nbsp;Hong-Gang Luo","doi":"10.1016/j.physe.2025.116385","DOIUrl":"10.1016/j.physe.2025.116385","url":null,"abstract":"<div><div>We investigate the thermoelectrical transport in a system of non-Hermitian double quantum dots. For that purpose, we set up a model where two quantum dots are experiencing gain and loss of energy and in proximity to two superconductors. By applying Keldysh Green’s function technique, we study the transmission function, conductance as well as the Seebeck coefficient. We calculate the thermoelectric quantities both analytically and numerically and show that a sign change of the Seebeck coefficient can occur when electrons transport through the Andreev bound states forming on the quantum dots. The sign change is induced by the competition of superconducting pairing potential and PT-symmetric complex potential, when the system passes through the exceptional point. These findings may be attractive for the study of quantum thermoelectric effects.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116385"},"PeriodicalIF":2.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267670","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":"Nonlinear corrections to the thermoelectric efficiency of a nanoscale device","authors":"Raymond J. Hartig ,&nbsp;Ioan Grosu ,&nbsp;Ionel Ţifrea","doi":"10.1016/j.physe.2025.116383","DOIUrl":"10.1016/j.physe.2025.116383","url":null,"abstract":"&lt;div&gt;&lt;div&gt;We investigate the nonlinear thermoelectric transport in a generic nanoscale device connected to two side reservoirs at different temperatures (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;) and chemical potentials (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;). We derive equations for the charge (electric) and heat (thermal) currents. These equations allow for the estimation of the second order contributions to the system’s thermoelectric response and the &lt;em&gt;analytical&lt;/em&gt; derivation of the first nonlinear contributions to the system’s electric conductance &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;σ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;, Seebeck coefficient &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;S&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;, and electronic thermal conductance &lt;span&gt;&lt;math&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;κ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;e&lt;/mi&gt;&lt;mi&gt;l&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt;. In the generation mode, when the system’s output power is positive (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;mo&gt;&gt;&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;), we estimate the maximum output power and efficiency of the system. The results are general and rely on generic dimensionless kinetic transport coefficients &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;K&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; that depends on the system’s characteristic electronic transmission function &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;τ&lt;/mi&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;E&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;. To outline the differences between the linear and nonlinear approximations we consider the particular case of a generalized Fano line-shape electronic transmission function and exactly calculate the dimensionless kinetic transport coefficients in terms of Hurwitz zeta functions and Bernoulli numbers. The output power efficiency of the system is estimated as function of the energy &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;ɛ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;E&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and broadening &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;γ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;Γ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;k&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; parameters. These results support the need for higher order terms in the theoretical analysis of the thermoelectric transport in nanoscale devices and allow for the optimization of the system’s propert","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116383"},"PeriodicalIF":2.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267668","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":"Voltage fluctuations in a four-terminal quantum device with orthogonal, unitary or symplectic symmetry","authors":"F. Castañeda-Ramírez ,&nbsp;M. Martínez-Mares ,&nbsp;A.M. Martínez-Argüello","doi":"10.1016/j.physe.2025.116386","DOIUrl":"10.1016/j.physe.2025.116386","url":null,"abstract":"<div><div>The statistical fluctuations of the voltage across a quantum wire in a four-terminal arrangement, where two of the terminals are used as probes while the other two are used to establish a flux current, is studied in the single channel case. The quantum wire to be measured consists of a chaotic microcavity or a disordered conductor in the presence of one of the three symmetry classes: orthogonal, unitary, or symplectic. Using the circular ensembles of random matrix theory or the Dorokov–Mello–Pereyra–Kumar (DMPK) equation, the statistical distribution of the voltage is reduced to quadratures for noninvasive probes which is solved numerically. Numerical simulations from random matrix theory or for the DMPK equation are performed for any coupling strength of the probes. For the chaotic cavity the effect of the symmetry class is clearly manifested through the weak and weak anti-localization phenomena for the orthogonal and symplectic symmetry classes, respectively. A similar effect is found, but with respect to the degree of disorder in a quantum wire as it evolves from strong to weak disorder: a simple correspondence between the label of the symmetry class and the degree of disorder, is found.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116386"},"PeriodicalIF":2.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267671","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":"Quantum Hall-like effect for neutral particles with magnetic dipole moments in a quantum dot","authors":"Carlos Magno O. Pereira,&nbsp;Edilberto O. Silva","doi":"10.1016/j.physe.2025.116381","DOIUrl":"10.1016/j.physe.2025.116381","url":null,"abstract":"<div><div>We predict a new class of quantum Hall phenomena in completely neutral systems, demonstrating that the interplay between radial electric fields and dipole moments induces exact <span><math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>/</mo><mi>h</mi></mrow></math></span> quantization without Landau levels or external magnetic fields. Contrary to conventional wisdom, our theory reveals that: (i) the singularity of line charges does not destroy topological protection, (ii) spin control of quantization emerges from boundary conditions alone, and (iii) the effect persists up to 25 K, surpassing typical neutral systems. These findings establish electric field engineering as a viable route to topological matter beyond magnetic paradigms.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116381"},"PeriodicalIF":2.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220919","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":"Strain-engineered electronic and thermoelectric properties of ZrX2 (X=S, Se) monolayers: A first-principles study","authors":"Khatir Ouail,&nbsp;Samia Ferahtia,&nbsp;Salima Saib,&nbsp;Nadir Bouarissa","doi":"10.1016/j.physe.2025.116384","DOIUrl":"10.1016/j.physe.2025.116384","url":null,"abstract":"<div><div>Through comprehensive first-principles calculations coupled with Boltzmann transport theory, we systematically investigate the strain-dependent structural, mechanical, electronic, and thermoelectric properties of monolayer ZrX₂ (X = S, Se). Our mechanical analysis reveals both materials maintain exceptional stability under biaxial strains ranging from −10 % to +10 %, with ZrS₂ exhibiting superior mechanical robustness as evidenced by its higher Young's modulus (73.95 N/m) compared to ZrSe₂ (63.70 N/m). Detailed electronic structure calculations employing the TB-mBJ potential demonstrate these monolayers are indirect band gap semiconductors, with fundamental gaps of 1.8 eV for ZrS₂ and 1.16 eV for ZrSe₂. Notably, compressive strain induces dramatic electronic transitions, reducing the band gap progressively until ZrSe₂ undergoes a complete semiconductor-to-metal transition at −10 % strain. The thermoelectric transport properties show remarkable strain sensitivity. Applied biaxial strain enhances the power factor by an order of magnitude, reaching exceptional values of 2.4 × 10¹¹ W/mK²s for ZrSe₂ at −6 % strain. Comparative analysis reveals n-type doping consistently outperforms p-type configurations in thermoelectric efficiency across all strain conditions. These enhancements originate from strain-induced modifications to both electronic band structures and carrier scattering mechanisms. Our combined mechanical, electronic, and thermoelectric characterization provides fundamental insights into the strain-response of ZrX₂ monolayers, demonstrating their exceptional tunability for next-generation flexible electronics, strain sensors, and high-efficiency energy conversion devices. The comprehensive dataset presented here establishes a foundation for future experimental investigations and device applications of these promising 2D materials.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116384"},"PeriodicalIF":2.9,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267672","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":"Broken sublattice symmetry induced gap opening of spin-polarized Dirac cone in MnF3","authors":"Limei Zheng,&nbsp;Yu Li,&nbsp;Dazhi Sun,&nbsp;Baozeng Zhou,&nbsp;Xiaocha Wang","doi":"10.1016/j.physe.2025.116382","DOIUrl":"10.1016/j.physe.2025.116382","url":null,"abstract":"<div><div>Two-dimensional (2D) transition-metal trihalides have received extensive attention in the field of novel spintronic devices and heterostructure coupling is an effective method for achieving multifunctional integration and regulation. In this work, using first-principles calculations, we systematically study the electronic structure and magnetic properties of the 2D MnF₃/graphene heterostructures. MnF₃ monolayer exhibits Dirac half-metal properties, with electron states featuring Dirac cones in its single spin channel. With different stacking configurations, the electronic properties of both are well preserved from the band structure, interfacial charge transfer only causes the relative movement of the electronic states. Additionally, due to the broken sublattice symmetry of MnF₃ in heterostructure, a gap opening of 24.9 meV appears around the spin-polarized Dirac cone in MnF₃. Moreover, the formation of heterostructure significantly enhances the in-plane magnetic anisotropy of the MnF₃ monolayer. By reducing the interlayer distance, the spin-polarized Dirac cone has a larger gap opening of 555.5 meV, which induces the transition of MnF₃ from Dirac half-metal to magnetic semiconductor, and the Curie temperature (<em>T</em>_C) increases obviously. Furthermore, a spin logic device based on MnF₃/graphene heterostructures is proposed, which can complete the resistive state switching from the \"1″ state to the \"0″ state by application of pressure. These results provide a reference for the application of MnF₃/graphene heterostructure in spintronic devices.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116382"},"PeriodicalIF":2.9,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220920","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":"Optical photonic diode realization through spatial self-phase modulation using Mn3O4 nanoparticles","authors":"K.V. Jayaprasad,&nbsp;Titu Thomas,&nbsp;Manu Vaishakh,&nbsp;Sheenu Thomas","doi":"10.1016/j.physe.2025.116378","DOIUrl":"10.1016/j.physe.2025.116378","url":null,"abstract":"<div><div>The growing demand for efficient nonlinear optical (NLO) materials for photonic devices such as isolators, switches, and telecommunication components necessitates the exploration of new nanostructured systems. Transition metal oxides like Mn₃O₄, with strong electronic interactions and thermal responses, remain relatively underexplored for their NLO behavior. In this work, Mn₃O₄ nanoparticles synthesized via ultrasonication-assisted precipitation were investigated using spatial self-phase modulation (SSPM) with a 532 nm CW DPSS laser. Structural and morphological characteristics were confirmed by XRD and TEM analyses. Nonlinear optical parameters, including the nonlinear refractive index (n₂) and thermo-optic coefficient <span><math><mrow><mfrac><mtext>dn</mtext><mrow><mi>d</mi><mspace></mspace><mi>T</mi></mrow></mfrac></mrow></math></span> , were determined from the variation of SSPM patterns with laser intensity. Furthermore, a photonic diode based on a cascaded Mn₃O₄/TiO₂ hybrid structure was demonstrated, enabling nonreciprocal light propagation through unidirectional SSPM excitation. These findings highlight Mn₃O₄ nanoparticles as promising candidates for NLO applications, while the proposed hybrid photonic diode offers potential in integrated optics, optical switching, and telecommunication technologies.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"175 ","pages":"Article 116378"},"PeriodicalIF":2.9,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220922","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}