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

{"title":"Strain-tunable electronic and optoelectronic properties of 2D MoS2 and its derivatives: A DFT study","authors":"Yikang Liu ,&nbsp;Songbo Xiong ,&nbsp;Zejiang Peng ,&nbsp;Qiuming Liu ,&nbsp;Mengqiu Long ,&nbsp;Tong Chen","doi":"10.1016/j.physe.2025.116439","DOIUrl":"10.1016/j.physe.2025.116439","url":null,"abstract":"<div><div>Two-dimensional transition metal-sulfur compound-derived materials have emerged as a significant research focus in the fields of condensed matter physics and optoelectronics, owing to their outstanding electronic, optical, thermal, and mechanical properties. In this study, we systematically investigate the electronic structures, density of states, optical properties, and optoelectronic performances of five 2D transition metal-sulfur compounds and their hydrogenation-derived monolayers, including MoS₂, MoSe₂, MoSSe, MoSH, and MoSeH, based on first-principles calculations. The results reveal that, under strain-free conditions, monolayer MoS₂ and MoSe₂ exhibit direct bandgap semiconductor characteristics with bandgap values of 1.75 eV and 1.53 eV, respectively. In contrast, the Janus MoSSe monolayer breaks the out-of-plane symmetry, resulting in the formation of an indirect bandgap of 1.21 eV, and its electronic properties undergo a semiconductor-to-metal transition under a compressive strain of 6 %. The hydrogenated derivatives MoSH and MoSeH display metallic behavior. The intrinsic MoS₂, MoSe₂, and MoSSe monolayers demonstrate excellent optical absorption characteristics under strain engineering. Based on these materials, p–i–n junction devices were further constructed, showing that MoS₂ and MoSe₂ possess strong absorption coefficients in the visible-light region, with peak values of 1.40 × 10⁷ cm⁻¹ and 1.14 × 10⁷ cm⁻¹, respectively. In comparison, MoSSe exhibits a pronounced absorption peak in the infrared region, reaching 1.59 × 10⁷ cm⁻¹, along with a remarkably high photoconductivity, making it a promising candidate for high-performance infrared photodetectors. Overall, this study provides a potential pathway toward the development of advanced optoelectronic devices based on these two-dimensional materials.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116439"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145682473","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 investigation of vacancy and doping effects on the magnetic and electronic properties of monolayer β-MoSi2N4","authors":"Yi Peng ,&nbsp;Fangyuan Li ,&nbsp;Qianqian Zhu ,&nbsp;Juexian Cao","doi":"10.1016/j.physe.2025.116447","DOIUrl":"10.1016/j.physe.2025.116447","url":null,"abstract":"<div><div>This study comprehensively examines how point defects (vacancies and substitutional doping) affect the magnetic, and electronic characteristics of β-MoSi₂N₄ monolayers using first-principles calculations. The analysis reveals that β-MoSi₂N₄ monolayers with vacancy defects V_Mo or V_N3Si display non-magnetic behavior, while V_N1, V_N2, V_NSi3, and V_Si introduce magnetic properties, with the magnetic moments primarily stemming from nearby atoms. Furthermore, the presence of these vacancies results in various electrical behaviors, categorizing them as semiconductors (V_Mo), metals (V_N3Si), magnetic semiconductors (V_N1), magnetic metals (V_NSi3), and half-metals (V_N2 and V_Si). In terms of substitutional doping, the incorporation of 3d transition metal atoms (TMs) at the silicon (Si) sites of β-MoSi₂N₄ monolayers generally induces magnetic characteristics, with notable exceptions for Sc, Ti, and Zn. The magnetic moments associated with TM impurities from V to Cu are calculated to be 1, 2, 3, 4, 3, 2, and 0.98 μ_B, respectively. Remarkably, the systems doped with V, Mn, and Cu attain 100 % spin polarization and exhibit distinctive half-metallic characteristics. These findings highlight the potential to leverage point defects to modulate the properties of monolayer β-MoSi₂N₄, with implications for developing advanced spintronic devices.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116447"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840162","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":"β-Irida-graphene: A new 2D carbon allotrope for sodium-ion battery anodes","authors":"José A.S. Laranjeira ,&nbsp;Kleuton A.L. Lima ,&nbsp;Nicolas F. Martins ,&nbsp;Luiz A. Ribeiro Junior ,&nbsp;Douglas S. Galvão ,&nbsp;Luis A. Cabral ,&nbsp;Julio R. Sambrano","doi":"10.1016/j.physe.2025.116442","DOIUrl":"10.1016/j.physe.2025.116442","url":null,"abstract":"<div><div>The quest for sustainable and efficient energy storage has driven the exploration of sodium-ion batteries (SIBs) as promising alternatives to lithium-ion systems. However, the larger ionic radius of sodium poses intrinsic challenges such as slow diffusion and structural strain in conventional electrode materials. As a contribution to addressing these limitations, the <span><math><mi>β</mi></math></span>-Irida-graphene (<span><math><mi>β</mi></math></span>-IG) is herein introduced, a novel two-dimensional (2D) carbon allotrope derived from Irida-graphene, featuring a diverse polygonal lattice of 3-, 4-, 6-, 8-, and 9-membered carbon rings. Through density functional theory and <em>ab initio</em> molecular dynamics simulations, <span><math><mi>β</mi></math></span>-IG demonstrated remarkable thermal, dynamical, and mechanical stability, coupled with intrinsic conductive character and efficient sodium-ion mobility (energy barriers <span><math><mrow><mo>&lt;</mo><mn>0</mn><mo>.</mo><mn>30</mn></mrow></math></span> eV). Furthermore, the adsorption of sodium ions was energetically favorable, delivering an impressive predicted specific capacity of 554.5 mAh/g. The reported findings highlight <span><math><mi>β</mi></math></span>-IG as a good potential anode candidate for next-generation SIBs, offering high-rate performance and structural robustness, and expanding the functional design space for advanced carbon-based electrode materials.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116442"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737371","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":"Enhanced dipole moment and absorption spectrum in CdSe nanoboomerang under external electric field","authors":"E.A. Vardanyan ,&nbsp;G.A. Mantashian ,&nbsp;N. Zeiri ,&nbsp;P.A. Mantashyan ,&nbsp;S. Thomas ,&nbsp;D.B. Hayrapetyan","doi":"10.1016/j.physe.2025.116443","DOIUrl":"10.1016/j.physe.2025.116443","url":null,"abstract":"<div><div>Boomerang-shaped semiconductor quantum nanostructures, also referred to as nanoboomerangs, offer unique optical and electronic properties due to their asymmetrical geometry, which enhances the spatial separation of charge carriers. This study investigates the influence of external electric fields on the excitonic states, dipole moments, and absorption spectra of these structures. Using the finite element method, we solve the Schrödinger equation to obtain the energy spectra and wave functions, which are then applied in a variational approach to model excitonic properties. The results reveal that the application of an electric field induces significant redshifts in the absorption spectrum due to the Stark effect, alongside variations in oscillator strengths. Strong overlap between wave functions of the same parity results in enhanced transitions, while mixed-parity transitions are amplified by the field-induced redistribution of charge carrier probability densities. The calculated dipole moments demonstrate field-dependent saturation behavior, reaching values as high as 725 Debye, attributable to the unique geometry of the boomerang-shaped nanostructures.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116443"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787202","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":"Ballistic transport and thermoelectric effect in gated phosphorene superlattices including Fibonacci-type aperiodicity","authors":"E.J. Guzmán ,&nbsp;O. Oubram ,&nbsp;O. Navarro ,&nbsp;I. Rodríguez-Vargas","doi":"10.1016/j.physe.2025.116449","DOIUrl":"10.1016/j.physe.2025.116449","url":null,"abstract":"<div><div>We theoretically study the thermoelectric effect in phosphorene nano-sheet when the ballistic transport is modulated by gated superlattices. The gating profile consists of electrostatic barriers arranged in periodic and aperiodic Fibonacci-type sequences along the armchair direction of phosphorene. We have calculated the transmission probability and conductance by using the transfer matrix method and Landauer-Büttiker formalism, respectively. We find that the transmission miniband structure of periodic superlattices is greatly fragmented and reduced by introduction of Fibonacci-type aperiodicity. Moreover, the conductance of Fibonacci-type supelattices shows a more pronounced oscillatory trend in contrast to periodic superlattices. Such significant changes in the conductance result in enhanced thermoelectric properties at low temperatures. We find peaks of Seebeck coefficient (<span><math><mi>S</mi></math></span>) in orders of <span><math><mrow><mn>0</mn><mo>.</mo><mn>1</mn><mo>−</mo><mn>0</mn><mo>.</mo><mn>35</mn></mrow></math></span> mV/K, with the highest peaks observed in aperiodic superlattices. Also, we obtain high values of figure of merit (<span><math><mrow><mi>Z</mi><mi>T</mi></mrow></math></span>) in the range of <span><math><mrow><mn>0</mn><mo>.</mo><mn>5</mn><mo>−</mo><mn>3</mn></mrow></math></span> and <span><math><mrow><mn>2</mn><mo>−</mo><mn>10</mn></mrow></math></span> for the periodic and aperiodic superlattices, respectively. Furthermore, we find extreme values of <span><math><mi>S</mi></math></span> (<span><math><mrow><mo>&gt;</mo><mn>1</mn></mrow></math></span> mV/K) and <span><math><mrow><mi>Z</mi><mi>T</mi></mrow></math></span> (<span><math><mrow><mo>&gt;</mo><mn>10</mn></mrow></math></span>) at energies very close to the bandgap in both (valence and conduction) bands. By analyzing the ratio of thermal and electronic conductances, we can identify the regions with optimized thermoelectric response. At 300 K, the thermoelectric response is considerably reduced (<span><math><mrow><mi>Z</mi><mi>T</mi><mo>≈</mo><mn>0</mn><mo>.</mo><mn>12</mn></mrow></math></span>) due to the thermal contribution of phonons. Our findings indicate that gated phosphorene superlattices could be the basis for high conversion efficiency thermoelectric devices.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116449"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840163","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":"The regulation of interface defects and photovoltaic performances of PbS/MAPbI3 core-shell nanorod arrays by quantum dot ligand","authors":"Peng Ye ,&nbsp;Yahong Wang ,&nbsp;Luming Zhou,&nbsp;Junying Yu,&nbsp;Lin He,&nbsp;Rongli Gao,&nbsp;Chunlin Fu","doi":"10.1016/j.physe.2025.116420","DOIUrl":"10.1016/j.physe.2025.116420","url":null,"abstract":"<div><div>The PbS quantum dots/MAPbI₃ core-shell nanorod array improves the photovoltaic performance by expanding the solar spectral absorption range and optimizing the carrier transport path, but the serious non-radiative recombination restriction efficiency caused by quantum dot/perovskite interface defects breaks through. Ligand modification is an effective post-processing strategy to passivate quantum dot defects. The MA⁺ and Pb²⁺ in the halogen ligand can be used as the intrinsic components of the perovskite and form hydrogen bonds with MAPbI₃ in situ, the short-chain characteristics eliminate the insulating barrier of the oleic acid ligand and increase the carrier mobility. In this paper, methylammonium iodide (MAI) and lead iodide (PbI₂) were used as passivators for the composite interface of nanorod arrays to explore the effects of different ligands on the composite interface, especially on perovskite. The results show that the MAI ligand system improves the interface defects of the infrared quantum dot/perovskite composite more prominently than the PbI₂ system. MA⁺ promotes the order of perovskite crystal orientation, improves the morphology, reduces the trap state, and improves the final photovoltaic conversion efficiency by 36 %. This work provides a new paradigm for the regulation of interface defects in PbS/MAPbI₃ composite solar cells through ligand chemical bond coordination strategy.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116420"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145600507","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":"Study of linear and nonlinear absorption and refractive index changes in multilayered spherical quantum dots for various excited states","authors":"A. Fakkahi ,&nbsp;Frankbelson dos S. Azevedo ,&nbsp;H. Azmi ,&nbsp;M. Jaouane ,&nbsp;J. El-Hamouchi ,&nbsp;A. Sali ,&nbsp;A. Ed-Dahmouny ,&nbsp;K. El-Bakkari ,&nbsp;R. Arraoui ,&nbsp;A. Mazouz ,&nbsp;M. Jaafar","doi":"10.1016/j.physe.2025.116445","DOIUrl":"10.1016/j.physe.2025.116445","url":null,"abstract":"<div><div>This study investigates the linear and nonlinear optical properties of multilayered spherical quantum dots by focusing on electronic transitions between the <span><math><mrow><mi>s</mi><mo>→</mo><mi>p</mi></mrow></math></span>, <span><math><mrow><mi>p</mi><mo>→</mo><mi>d</mi></mrow></math></span>, and <span><math><mrow><mi>d</mi><mo>→</mo><mi>f</mi></mrow></math></span> states. Using the Finite Element Method (FEM) within the Effective Mass Approximation (EMA), we calculate the linear, third-order nonlinear, and total optical absorption coefficients, as well as the corresponding changes in the refractive index. Our results reveal distinct spectral features associated with each type of transition, highlighting the influence of quantum confinement on the absorption and refractive index behavior. In particular, we find that the nonlinear optical response becomes increasingly significant for higher excited-state transitions, where the third-order nonlinear absorption may surpass the linear contribution in the vicinity of resonance. This behavior is observed across multiple excitation pathways, indicating that the dominance of nonlinear effects may be a general feature associated with transitions involving larger spatial extension of the electronic wavefunctions. The interplay between these transitions governs the overall optical response of the quantum dots, providing insight into their potential applications in optoelectronic and nanophotonic devices. These results suggest that multilayered spherical quantum dots can be engineered to selectively enhance nonlinear optical processes, making them promising candidates for the development of tunable, intensity-dependent photonic components.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116445"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145840169","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":"Cobalt-induced Multifunctionality: Ferromagnetism and tunable optoelectronic properties in hydrothermally synthesized SnS2 nanoparticles","authors":"Anjali Bhattacharyya,&nbsp;Madhusudhana Rao N,&nbsp;Basit Iqbal,&nbsp;Purnendu Ray","doi":"10.1016/j.physe.2025.116435","DOIUrl":"10.1016/j.physe.2025.116435","url":null,"abstract":"<div><div>Research into Diluted Magnetic Semiconductors (DMS) has experienced significant advancement over the past decade. This progress is largely attributable to the development of sophisticated synthesis techniques, which have enabled the fabrication of high-quality samples with well-characterized properties for experimental study. Consequently, DMS are widely regarded as a leading material platform for the development of spintronic devices. This study comprehensively investigates the first-principles study of SnS₂ and structural, morphological, chemical, optical, and magnetic properties of hydrothermally prepared pure and Cobalt-doped SnS₂ (1 %, 3 %, 5 %, 7 %) nanoparticles. X-ray diffraction analysis confirms the preservation of the hexagonal crystal phase post-doping. In contrast, Williamson-Hall (W-H) plot analysis indicates an increase in crystallite size from 32.9 nm to 66.8 nm with Co concentration. FESEM reveals a nanoflower-like morphology. X-ray photoelectron spectroscopy verifies the presence of Sn⁴⁺ and S²⁻ states and confirms the successful incorporation of Co dopants, which exhibit mixed Co²⁺/Co³⁺ oxidation states. Optical characterization demonstrates a reduction in reflectance and a narrowing of the optical band gap from 2.26 eV to 1.56 eV with doping. Density functional theory shows that the band gap of pure SnS₂ is direct. The Urbach energy, initially increasing up to 3 % Co doping, suggests a rise in structural disorder, followed by a subsequent decrease. A reduction in the refractive index from 4.62 to 3.10 indicates enhanced optical transmission, while a increase in optical and decrease in electrical conductivity is observed. The tunability of the emission wavelength across the visible spectrum, as observed in the photoluminescence (PL) spectra, is directly enabled by Co-doping. This controllability underscores the material's strong potential for application in advanced optoelectronic devices. Furthermore, the observed hysteresis loop confirms the emergence of ferromagnetic ordering upon cobalt doping. These findings collectively demonstrate that Cobalt-doped SnS₂ is a promising diluted magnetic semiconductor (DMS) material, whose tunable properties make it a strong candidate for application in spintronics and multifunctional optoelectronic devices.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116435"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145737372","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":"Broadband perfect absorber based on graphene-silicon Mie heterojunctions for cancer cell detection","authors":"Qingbing Yang ,&nbsp;Lili Zeng ,&nbsp;Minghua Wang ,&nbsp;Bingwei Guo ,&nbsp;Yufan Deng ,&nbsp;Shuxin Xu ,&nbsp;Boxun Li","doi":"10.1016/j.physe.2025.116456","DOIUrl":"10.1016/j.physe.2025.116456","url":null,"abstract":"<div><div>In this paper, a composite architecture is pioneered, comprising a three-layer heterostructure of patterned graphene and silicon cylinder-embedded dielectric. To leverage strong Mie resonances triggered by embedded silicon pillars, an octagonal–cross–octagonal stacked graphene configuration is introduced. The key innovation is the demonstration of synergistic triple-mode coupling among Mie resonance, plasmonic mode, and Fabry–Pérot cavity resonance in the terahertz regime, which seamlessly fuses multiple discrete absorption peaks into a broadband spectrum. The absorber achieves an unprecedented absorption exceeding 96 % within 6.22–11.62 THz, setting a bandwidth record of 5.40 THz (fractional bandwidth of 60.5 %), with absorption over 98 % sustained across a 1.86 THz sub-band. Dynamic modulation of absorption characteristics is readily attainable by adjusting graphene's Fermi level and relaxation time. The absorption remains robust for incident angles up to 22.92°owing to its rotationally symmetric design, effectively eliminating angle dependence. Pushing the frontier further, this structure is innovatively harnessed for biomedical sensing, where the redshift of resonance peaks enables clear differentiation between healthy cells and breast cancer cells. Traditional methods primarily rely on monitoring the shifts of resonance peaks or dips, while this study, leveraging the field enhancement properties of the structure, further proposes a new sensitivity metric based on changes in absorption intensity for dual verification. It is this dual mechanism that ultimately achieves a high sensitivity of 4.29 THz/RIU and an intensity sensitivity of 55.89 %, opening up a new pathway for terahertz biosensing applications. This work transcends the longstanding trade-off between bandwidth and tunability in conventional terahertz absorbers, opening up a new pathway for terahertz biosensing applications.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116456"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884276","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":"Optically controlled high-performance terahertz modulator enabled by GeSe2/Si heterojunctions","authors":"Tong Lv ,&nbsp;Qifubo Geng ,&nbsp;Xunjun He ,&nbsp;Mingze Zhang ,&nbsp;Sergey Maksimenko","doi":"10.1016/j.physe.2025.116448","DOIUrl":"10.1016/j.physe.2025.116448","url":null,"abstract":"<div><div>In this study, we fabricated a broadband terahertz (THz) modulator based on an optically controlled GeSe₂/Si heterojunction via magnetron sputtering and vacuum selenization. The structural and morphological properties of the fabricated GeSe2 film were characterized using XRD, Raman, SEM, and AFM. Under 532 nm laser excitation, the device exhibited a modulation depth more seven times higher than that of bare silicon. At a pump density of 1500 mW/cm², effective modulation was achieved over a broad bandwidth of 0.2–1 THz, with a maximum modulation depth of ∼60 % at 1 THz. Systematic analysis revealed that the enhanced modulation performance originates from efficient separation and accumulation of photogenerated carriers at the heterojunction interface. Therefore, this study not only provides fundamental insights into the optoelectronic dynamics of GeSe₂-based heterostructures, but also supports their potential for application in advanced THz devices, including modulators, filters, and polarizers.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"177 ","pages":"Article 116448"},"PeriodicalIF":2.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787220","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}