Physica B-condensed Matter最新文献

{"title":"Non-toxic KGeX3 (X= I, Br, Cl) monolayer perovskites as an absorption layer in solar energy converters: A first principle study","authors":"Vandana B. Parmar,&nbsp;P.N. Gajjar,&nbsp;A.M. Vora","doi":"10.1016/j.physb.2025.417023","DOIUrl":"10.1016/j.physb.2025.417023","url":null,"abstract":"<div><div>The study of Ge-based perovskite materials aims to reduce pollution and create highly efficient perovskite-based solar cells. We investigate the structural, electronic, and optical properties of bulk and monolayer forms of KGeX₃ (where X = I, Br, or Cl) perovskites using density functional theory (DFT). Phonon dispersion curves confirm the dynamic stability of KGeX₃. Several materials in the field exhibit direct bandgap semiconductor properties. As we progress from I to Br and from Br to Cl in KGeX₃, there is a clear trend of increasing bandgap values. The static dielectric constant of KGeI₃ is higher than that of KGeBr₃ and KGeCl₃, indicating a lower carrier recombination rate. A redshift is also observed in the absorption coefficient data as the transition in KGeX₃ progresses from Cl → Br → I. The efficiencies of bulk KGeI₃, KGeBr₃, and KGeCl₃ were estimated to be approximately 15.57 %, 23.43 %, and 31.70 %, respectively, using the Shockley-Queisser (SQ) limit. For monolayer forms, the efficiencies of KGeI₃, KGeBr₃, and KGeCl₃ were found to be approximately 28.77 %, 32.38 %, and 22.99 %, respectively. The KGeX₃ nanoparticle structure is promising for the light-absorbing layer in solar photovoltaic applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 417023"},"PeriodicalIF":2.8,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437062","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 transport in double finger gate devices under AC plus DC voltage gate control","authors":"Moh-Erlangga-Aditya Rifandi ,&nbsp;Quoc-Hung Phan ,&nbsp;Chi-Shung Tang ,&nbsp;Nzar Rauf Abdullah ,&nbsp;Vidar Gudmundsson","doi":"10.1016/j.physb.2025.416978","DOIUrl":"10.1016/j.physb.2025.416978","url":null,"abstract":"<div><div>A scattering matrix method is employed to investigate the quantum transport in the two-dimensional electron gas of an n-type split-gate quantum device with double finger gates under combined AC and DC voltage gate control. The investigation focuses specifically on the effects of four parameters on the quantum conductance: the DC potential amplitude, the AC potential amplitude, the distance between the two finger gates, and the effective photon energy. The results reveal that all four parameters have a profound effect on the quantum conductance outcomes and lead to the formation of different quasi-bound states and resonance peaks. The theoretical analysis conducted in this study provides useful guidance for the design of n-type gate-controlled devices with AC+DC-controlled double finger gates.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 416978"},"PeriodicalIF":2.8,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418907","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":"Numerical simulation of Cs2AgInBr6/Cs4CuSb2Cl12 heterojunction perovskite solar cell: A path to achieve optimized performance","authors":"Sofia Tahir ,&nbsp;Shammas Mushtaq ,&nbsp;Rabia Saeed ,&nbsp;Javed Iqbal ,&nbsp;M.D. Alshahrani ,&nbsp;Rasmiah S. Almufarij ,&nbsp;Islam Ragab ,&nbsp;Arslan Ashfaq","doi":"10.1016/j.physb.2025.417011","DOIUrl":"10.1016/j.physb.2025.417011","url":null,"abstract":"<div><div>In a recent study, inorganic perovskite solar cells based on Cesium continually enhanced solar cell performance. The exceptional stability and performance of the Cs₂AgInBr₆ layer in all-inorganic PSCs make it stand out among the other materials. Unfortunately, the Cs₂AgInBr₆ leads to poor solar energy utilization, significantly reducing light absorption. Based on the matching band structures of Cs₄CuSb₂Cl₁₂ and Cs₂AgInBr₆, the present simulation suggests that Cs₂AgInBr₆/Cs₄CuSb₂Cl₁₂ heterojunction incorporating Cs₄CuSb₂Cl₁₂ rather than HTL. It is then optimized and simulated using simulation software SCAPS-1D to improve sunlight absorption as well as solar cell performance. The open circuit voltage (V_oc) of the Cs₄CuSb₂Cl₁₂ layer is very large compared to other materials due to its wide bandgap (1.6 eV). The large value of V_oc for the proposed heterojunction perovskite solar cell gives a large value of power conversion efficiency. In the final or optimized structure of the heterojunction solar cell, the thickness of Cs₂AgInBr₆ and Cs₄CuSb₂Cl₁₂ layers were selected as 1000 nm and 200 nm, respectively. The Cs₂AgInBr₆ layer had a doping concentration of 1 × 10¹⁷cm³, N_T of 1 × 10¹⁰cm³, and an E_g of 1.47 eV. The Cs₄CuSb₂Cl₁₂ layer has a band gap of 1.6 eV, a defect density of 1 × 10¹⁰ cm³, and an N_A of 1 × 10²⁰ cm⁻³. After the optimization study, the device operates at an ideal stage where V_oc (V) = 1.225, J_sc (mA/cm²) = 29.037, FF (%) = 89.42, and PCE (%) = 31.83. The optimized Cs₂AgInBr₆/Cs₄CuSb₂Cl₁₂ heterojunction has a device efficiency of 31.83 %, which is considerably greater than the power conversion efficiency of 12.91 % for a single layer of Cs₂AgInBr₆. Thus, this study shows that the Cs₂AgInBr₆/Cs₄CuSb₂Cl₁₂ heterojunction PSCs can pave the way for the promising afterward of Cs-based PSCs for real-world uses in optoelectronics and photovoltaics.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 417011"},"PeriodicalIF":2.8,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437061","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 magnetic field on the nonlinear optical properties of ZnO/Zn1−xMgxO pyramid quantum dots in the presence of an off-center impurity","authors":"A. Bakdid ,&nbsp;S. Chouef ,&nbsp;M. Hbibi ,&nbsp;R. Boussetta ,&nbsp;A. El Moussaouy ,&nbsp;O. Mommadi ,&nbsp;C.A. Duque","doi":"10.1016/j.physb.2025.417001","DOIUrl":"10.1016/j.physb.2025.417001","url":null,"abstract":"<div><div>The present work explores the influence of magnetic field on the optical properties of <span><math><mrow><mi>ZnO</mi><mo>/</mo><msub><mrow><mi>Zn</mi></mrow><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub><msub><mrow><mi>Mg</mi></mrow><mrow><mi>x</mi></mrow></msub><mi>O</mi></mrow></math></span> pyramid quantum dot in the presence of an off-center donor atom. The theoretical study, carried out using the finite element method, reveals that the geometry of the quantum dot and the location of the impurity considerably affect the electron energies transition, oscillator strength and the optical absorption coefficients under the effect of the magnetic field. The results show that magnetic fields significantly modify energy transitions and linear and non-linear absorption coefficients. Also, the relative refractive coefficients have been affected by impurity position and magnetic field effect, which opened the way to advanced applications in optoelectronics, such as UV sensors and light-emitting diodes, where control of optical properties is essential to improve the performance of emerging technologies.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 417001"},"PeriodicalIF":2.8,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418890","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":"Temperature dependence of structural, elastic and thermodynamic properties of X2PtH6 (X=Li and Na) from first principles calculation","authors":"H. Ziani ,&nbsp;A. Gueddim ,&nbsp;N. Bouarissa","doi":"10.1016/j.physb.2025.417020","DOIUrl":"10.1016/j.physb.2025.417020","url":null,"abstract":"<div><div>X₂PtH₆ (X = Li, Na) are promising materials for hydrogen storage. For this, their structural, elastic and thermodynamic properties at different temperatures were studied. Our calculations are carried out within the framework of the full potential-linearized augmented plane wave method. Our obtained data show that the stiffness of Li₂PtH₆ compound material is higher than that of Na₂PtH₆. The elastic constants of the compound material Li₂PtH₆ are higher than those of Na₂PtH₆. Increasing the temperature from 0 to 1500 K, decreases the Debye temperature, indicating the decrease in its higher thermal conductivity. The same behavior has been reported for the Gibbs free energy with temperature. Among these materials, Na₂PtH₆ has the smallest Gibbs free energy, suggesting its superior forming ability. Li₂PtH₆ has the highest shear and Young's modulus due to its strong chemical bonding. Li₂PtH₆ exhibits the lowest degree of anisotropy due to the lack of strong direction in the bond. However, at constant volume, the specific heat capacities, the coefficient of thermal expansion and the change in entropy increase with increasing temperature.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 417020"},"PeriodicalIF":2.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418976","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":"Electronic and optical properties of monolayer Si2HX (X=F, Cl, Br, I) with high absorption and strong exciton effect","authors":"Xinyang Li ,&nbsp;Xinyu Wang ,&nbsp;Xiaolei Li ,&nbsp;Dayong Liu ,&nbsp;Xiaoshan Wu ,&nbsp;Huailiang Fu ,&nbsp;Chonggui Zhong","doi":"10.1016/j.physb.2025.417022","DOIUrl":"10.1016/j.physb.2025.417022","url":null,"abstract":"<div><div>This paper researched the structure, optical and electronic properties of monolayer Si₂HX (X = F, Cl, Br, I) with asymmetric structure. We found that all monolayer Si₂HX are the direct-gap semiconductors, and are dynamically, thermally and mechanically stable. The in-plane isotropic Young's modulus of 52.39–60.43 N/m and Poisson's ratio of about 0.24 for Si₂HX reveal their remarkable flexibility. For Si₂HF, the electron mobility of 18410.92 <span><math><mrow><mi>c</mi><msup><mi>m</mi><mn>2</mn></msup><msup><mrow><mo>∙</mo><mi>V</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>∙</mo><msup><mi>s</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> is much greater than that of graphene. By Bethe-Salpeter equation (BSE) method considering the electron-hole interactions, we obtained the optical absorption spectrum of Si₂HX. It is found that the absorption spectrum shows a strong exciton effect and a wide absorption range with the optical band gap of 1.56–2.27 eV. Moreover, the large absorbance of monolayer Si₂HCl can be up to 17 % in the visible region. The research shows that the monolayer asymmetric Si₂HX is promising for high-performance, ultra-thin and flexible optoelectronic devices and photocatalysis.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 417022"},"PeriodicalIF":2.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418978","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 on the geometric structures and properties of MB2n− (M=V, Cr, Ni; n=8–12) based on the first-principles calculations","authors":"Jun-Cui Zhao ,&nbsp;Cheng-Gang Li ,&nbsp;Chun-Jia Yang ,&nbsp;Bo Du ,&nbsp;Zhen Sun ,&nbsp;Yi-Ming Zhang ,&nbsp;Hao Tian ,&nbsp;Da Teng","doi":"10.1016/j.physb.2025.417021","DOIUrl":"10.1016/j.physb.2025.417021","url":null,"abstract":"<div><div>Here, we undertook a comprehensive investigation into the geometric structures and properties of MB_2n⁻ (M = V, Cr, Ni; n = 8–12) clusters. Initially, using first-principles calculations along with the CALYPSO structural searching method, the global minimum structures of B_2n⁻ and MB_2n⁻ (M = V, Cr, Ni; n = 8–12) clusters were optimized. A comparative analysis elucidated that the incorporation of transition metal atoms induces a complete structural rearrangement of pure boron clusters, leading to the formation of drum-like and cage-like structures, respectively. Subsequently, based on the global minimum structures, the PES, IR and Raman spectra were simulated by Multiwfn software. These simulations offer invaluable guidance for the experimental identification and characterization. In addition, we conducted a systematic examination of the stabilities, charge transfer, magnetic properties and atomic orbital. In conclusion, our research not only provides profound theoretical insights to inform and direct experimental investigations but also contributes novel perspectives and empirical evidence to the broader theoretical framework.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 417021"},"PeriodicalIF":2.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143430299","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":"Band alignment modulation of two-dimensional XTe2(X=Mo, W)/Al2S3 ferroelectric van der Waals heterostructures","authors":"Yuping Wang ,&nbsp;Peize Yuan ,&nbsp;Xueping Li ,&nbsp;Jianye Wang ,&nbsp;Ding Wang ,&nbsp;Congxin Xia","doi":"10.1016/j.physb.2025.416999","DOIUrl":"10.1016/j.physb.2025.416999","url":null,"abstract":"<div><div>Two-dimensional ferroelectric van der Waals heterostructures (vdWHs) have introduced a promising paradigm for the development of nano-electronic devices in the fields of sensor-memory and computing integration applications. Here, we propose an XTe₂(X = Mo, W)/Al₂S₃ ferroelectric vdWHs, taking into account the regulation of band alignment by the electric field, biaxial strain and interlayer distance. The polarization reversal of Al₂S₃ triggers a transformation in the band alignment of the XTe₂/Al₂S₃ vdWHs from type-I to type-III. Moreover, by applying external electric fields and biaxial strains, the band alignment type of the XTe₂/Al₂S₃ vdWHs can be flexibly switched between type-I, type-II, and type-III. Especially, the band alignments are robust to within a certain range of interlayer distance. The results provide guidance for future experimental manipulation of two-dimensional ferroelectric heterostructure and related device applications.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 416999"},"PeriodicalIF":2.8,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418979","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 optical, dielectric, and magnetic characteristics of Praseodymium and Bismuth Co-doped Yttrium iron garnet ceramics","authors":"M. Bhargavi ,&nbsp;J. Kaarthik ,&nbsp;Salla Gangi Reddy ,&nbsp;Annapureddy Venkateswarlu","doi":"10.1016/j.physb.2025.417019","DOIUrl":"10.1016/j.physb.2025.417019","url":null,"abstract":"<div><div>Praseodymium (Pr) and Bismuth (Bi) co-doped Yttrium Iron Garnet (Pr_xBiY_2-xFe₅O₁₂, where x = 0.1, 0.25, 0.5, and 1.0) nanoparticles were synthesized via a self-combustion-assisted sol-gel method. Structural analysis confirmed the formation of a pure cubic Y₃Fe₅O₁₂ (YIG) phase without any secondary phases. Morphological characterization and energy dispersive spectroscopy (EDS) confirmed the successful incorporation of Pr³⁺ and Bi³⁺ ions into the YIG ferrite structure. Optical measurements showed a decreased optical band gap attributed to new energy levels introduced by Pr³⁺ doping. Magnetic characterization exhibited typical ferrimagnetic behaviour, with reduced saturation magnetization, coercive field, and anisotropy constant as Pr³⁺ content increased, indicating disruption in magnetic alignment. While challenges remain in balancing enhanced dielectric properties with reduced magnetic alignment and ensuring stability for practical applications, the composition with x = 0.25 demonstrated balanced magneto-dielectric properties. This makes it a promising candidate for multifunctional microwave applications such as filters and resonators.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"703 ","pages":"Article 417019"},"PeriodicalIF":2.8,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418977","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":"Electronic and optical response of lithium battery cathode Li(Mn/Co)O2: Compton spectroscopy, Gaussian and muffin-tin DFT computations","authors":"B.L. Ahuja ,&nbsp;B.L. Choudhary ,&nbsp;Kishor Kumar ,&nbsp;Jagrati Sahariya ,&nbsp;Ushma Ahuja ,&nbsp;Amit Soni ,&nbsp;Pooja K. Joshi ,&nbsp;Lekhraj Meena ,&nbsp;N.L. Heda","doi":"10.1016/j.physb.2025.417006","DOIUrl":"10.1016/j.physb.2025.417006","url":null,"abstract":"<div><div>A systematic comparison of electronic and optical properties of LiMnO₂ and LiCoO₂ has been reported using linear combination of atomic orbitals (LCAO) and full potential linearized augmented plane wave (FP-LAPW) with Hubbard parameter U = 0 and 4–7. Both approximations show LiMnO₂ and LiCoO₂ as semiconductors. LCAO scheme has also been exercised to compute Mulliken's population (MP) and Compton profiles (CPs) using different exchange-correlations potentials. A comparison of measured CPs of both cathode materials using ²⁴¹Am Compton spectrometer and LCAO based profiles show usefulness of hybrid (B3LYP) scheme. Here, semiconductor properties of both oxides are due to majority spin d states of Mn and Co and minority spin O-2p states. Delocalisation of 3d orbitals of Mn and Co and bonding characteristics of the oxides have been discussed using MP and equally normalised CPs. The dielectric functions and absorption coefficients show added utility of LiMnO₂ in photovoltaics and LiCoO₂ in ultraviolet detectors.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":"702 ","pages":"Article 417006"},"PeriodicalIF":2.8,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421331","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}