Pub Date : 2024-11-16DOI: 10.1016/j.ssc.2024.115760
S. Elkhouad , Z. Yamkane , M. Sadik , R. Moubah , M. Moutataouia , H. Lassri , L. Bessais , J. Horcheni , H. Jaballah , M. Abdellaoui
Sr0.54Ca0,46Fe6.5-xNixAl5.5O19 (0 ≤ x ≤ 0.3) hexaferrite powders were prepared by the sol-gel auto combustion method and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Magnetic measurements were performed with physical properties measurement system (PPMS). The lattice parameters, volume, and lattice strain were calculated. XRD analyses revealed a reduction in crystallite size with increasing Ni content. Interestingly, the magnetic analysis indicated that nickel, with its low magnetic moment, significantly enhanced the magnetization of Sr0.54Ca0.46Fe6.5-xNixAl5.5O19 (0.0 ≤ x ≤ 0.3) and reduced the coercive field. Furthermore, the Law of Approach to Saturation (LAS) theory was employed to extract the first anisotropy constant, the anisotropy field, and several essential magnetic parameters, providing valuable insights into the magnetic behavior of samples.
采用溶胶-凝胶自动燃烧法制备了 Sr0.54Ca0,46Fe6.5-xNixAl5.5O19 (0 ≤ x ≤ 0.3) 六价铁氧体粉末，并使用 X 射线衍射 (XRD)、扫描电子显微镜 (SEM) 和能量色散 X 射线光谱 (EDX) 对其进行了表征。磁性测量采用物理性质测量系统（PPMS）进行。计算了晶格参数、体积和晶格应变。XRD 分析表明，随着镍含量的增加，晶粒尺寸减小。有趣的是，磁性分析表明，镍的低磁矩显著增强了 Sr0.54Ca0.46Fe6.5-xNixAl5.5O19（0.0 ≤ x ≤ 0.3）的磁化，并降低了矫顽力场。此外，还利用饱和定律（LAS）理论提取了第一各向异性常数、各向异性场和几个基本磁性参数，为了解样品的磁性行为提供了宝贵的见解。
{"title":"Tailoring structural, morphological, and magnetic properties of Sr0.54Ca0.46Fe6.5-xNixAl5.5O19 hexaferrites via Ni substitution","authors":"S. Elkhouad , Z. Yamkane , M. Sadik , R. Moubah , M. Moutataouia , H. Lassri , L. Bessais , J. Horcheni , H. Jaballah , M. Abdellaoui","doi":"10.1016/j.ssc.2024.115760","DOIUrl":"10.1016/j.ssc.2024.115760","url":null,"abstract":"<div><div>Sr<sub>0.54</sub>Ca<sub>0,46</sub>Fe<sub>6.5-x</sub>Ni<sub>x</sub>Al<sub>5.5</sub>O<sub>19</sub> (0 ≤ x ≤ 0.3) hexaferrite powders were prepared by the sol-gel auto combustion method and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Magnetic measurements were performed with physical properties measurement system (PPMS). The lattice parameters, volume, and lattice strain were calculated. XRD analyses revealed a reduction in crystallite size with increasing Ni content. Interestingly, the magnetic analysis indicated that nickel, with its low magnetic moment, significantly enhanced the magnetization of Sr<sub>0.54</sub>Ca<sub>0.46</sub>Fe<sub>6.5-x</sub>Ni<sub>x</sub>Al<sub>5.5</sub>O<sub>19</sub> (0.0 ≤ x ≤ 0.3) and reduced the coercive field. Furthermore, the Law of Approach to Saturation (LAS) theory was employed to extract the first anisotropy constant, the anisotropy field, and several essential magnetic parameters, providing valuable insights into the magnetic behavior of samples.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"396 ","pages":"Article 115760"},"PeriodicalIF":2.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-15DOI: 10.1016/j.ssc.2024.115759
Md. Rabbi Talukder , Wahidur Rahman Sajal , Md. Safin Alam , Fatema-Tuz -Zahra , Jahirul Islam
In the field of optoelectronic applications, inorganic cubic halide perovskites have turned into a leading choice for commercialization. The physical properties of cubic FrMI3 (M = Ge, Sn) halide perovskites under pressure are explored at multiple pressures up to 10 GPa using ab initio Density-Functional Theory due to their significant importance. The structural accuracy, reflected in lattice parameters and unit cell volume, closely corresponds to previously reported data. FrGeI3 and FrSnI3 exhibited direct electronic band gaps of 0.65 eV and 0.46 eV with GGA-PBE functional, respectively, indicating their semiconducting nature at 0 GPa. The enhanced band gaps obtained employing the HSE06 potential are 1.61 eV and 1.28 eV for the corresponding perovskites. FrGeI3 and FrSnI3 shift from semiconducting to metallic states under pressures of 4.5 GPa and 3 GPa, respectively, thereby enhancing the conductivity. Pressure also improves optical functions, indicating both perovskites may be employed in high-efficiency optoelectronic devices that operate within the visible and ultra-violet (UV) range. At 10 GPa pressure, both FrGeI3 and FrSnI3 demonstrate the sharpest absorption spikes in the UV region, approximately at 2.61 × 105 cm−1 and 2.42 × 105 cm−1, respectively, resulting in sharp peaks in optical conductivity of approximately 5.98 1/fs for FrGeI3 and 5.49 1/fs for FrSnI3. FrGeI3 consistently outperforms FrSnI3, offering superior electronic and optical characteristics. Additionally, pressure modifies the mechanical features of entitled perovskites while conserving stability. The anisotropic and ductile properties become more pronounced under pressure. The outcomes of this study are expected to propel the advancement of lead-free optoelectronic devices, driving innovation in sustainable energy solutions.
{"title":"Tuning band gap and improving optoelectronic properties of lead-free halide perovskites FrMI3 (M = Ge, Sn) under hydrostatic pressure","authors":"Md. Rabbi Talukder , Wahidur Rahman Sajal , Md. Safin Alam , Fatema-Tuz -Zahra , Jahirul Islam","doi":"10.1016/j.ssc.2024.115759","DOIUrl":"10.1016/j.ssc.2024.115759","url":null,"abstract":"<div><div>In the field of optoelectronic applications, inorganic cubic halide perovskites have turned into a leading choice for commercialization. The physical properties of cubic FrMI<sub>3</sub> (M = Ge, Sn) halide perovskites under pressure are explored at multiple pressures up to 10 GPa using ab initio Density-Functional Theory due to their significant importance. The structural accuracy, reflected in lattice parameters and unit cell volume, closely corresponds to previously reported data. FrGeI<sub>3</sub> and FrSnI<sub>3</sub> exhibited direct electronic band gaps of 0.65 eV and 0.46 eV with GGA-PBE functional, respectively, indicating their semiconducting nature at 0 GPa. The enhanced band gaps obtained employing the HSE06 potential are 1.61 eV and 1.28 eV for the corresponding perovskites. FrGeI<sub>3</sub> and FrSnI<sub>3</sub> shift from semiconducting to metallic states under pressures of 4.5 GPa and 3 GPa, respectively, thereby enhancing the conductivity. Pressure also improves optical functions, indicating both perovskites may be employed in high-efficiency optoelectronic devices that operate within the visible and ultra-violet (UV) range. At 10 GPa pressure, both FrGeI<sub>3</sub> and FrSnI<sub>3</sub> demonstrate the sharpest absorption spikes in the UV region, approximately at 2.61 × 10<sup>5</sup> cm<sup>−1</sup> and 2.42 × 10<sup>5</sup> cm<sup>−1</sup>, respectively, resulting in sharp peaks in optical conductivity of approximately 5.98 1/fs for FrGeI<sub>3</sub> and 5.49 1/fs for FrSnI<sub>3</sub>. FrGeI<sub>3</sub> consistently outperforms FrSnI<sub>3</sub>, offering superior electronic and optical characteristics. Additionally, pressure modifies the mechanical features of entitled perovskites while conserving stability. The anisotropic and ductile properties become more pronounced under pressure. The outcomes of this study are expected to propel the advancement of lead-free optoelectronic devices, driving innovation in sustainable energy solutions.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"396 ","pages":"Article 115759"},"PeriodicalIF":2.1,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-14DOI: 10.1016/j.ssc.2024.115758
Fatemeh Badieian Baghsiyahi, Mahbubeh Yeganeh
In this work, electronic structure and optical properties of Fe-doped TiO2 at Fe/Ti ratios of 0, 5, 8.3, and 10 % were investigated based on density functional theory. The appearance of the asymmetrical patterns in the spin-polarized density of states of the doped samples reveals the occurrence of magnetism due to doping. The presence of impurity levels in the spin-up channel by hybridization of the O 2p, Fe 3d, and Ti 3d results in the reduction of the band gap in Fe-doped samples. The optical properties in spin-up channels showed significant changes at low energy regions (<2.5 eV), and optical absorption is found to increase by Fe doping.
在这项研究中，基于密度泛函理论研究了铁/钛比为 0%、5%、8.3% 和 10% 的掺铁二氧化钛的电子结构和光学特性。掺杂样品自旋极化态密度中出现的不对称图案揭示了掺杂导致的磁性。由于 O 2p、Fe 3d 和 Ti 3d 的杂化，自旋上升通道中出现了杂质水平，导致掺杂铁的样品带隙减小。自旋上升沟道中的光学特性在低能区（2.5 eV）发生了显著变化，掺杂铁后光吸收增加。
{"title":"The theoretical investigation of the electronic and optical properties of Fe-doped anatase TiO2","authors":"Fatemeh Badieian Baghsiyahi, Mahbubeh Yeganeh","doi":"10.1016/j.ssc.2024.115758","DOIUrl":"10.1016/j.ssc.2024.115758","url":null,"abstract":"<div><div>In this work, electronic structure and optical properties of Fe-doped TiO<sub>2</sub> at Fe/Ti ratios of 0, 5, 8.3, and 10 % were investigated based on density functional theory. The appearance of the asymmetrical patterns in the spin-polarized density of states of the doped samples reveals the occurrence of magnetism due to doping. The presence of impurity levels in the spin-up channel by hybridization of the O 2p, Fe 3d, and Ti 3d results in the reduction of the band gap in Fe-doped samples. The optical properties in spin-up channels showed significant changes at low energy regions (<2.5 eV), and optical absorption is found to increase by Fe doping.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"396 ","pages":"Article 115758"},"PeriodicalIF":2.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-13DOI: 10.1016/j.ssc.2024.115757
S. Sai Krupa , D. Surya Reddy , V. Rajagopal Reddy , Chel-Jong Choi
This work examines the structural and chemical characteristics of spin-coated magnesium oxide (MgO) on undoped InP (un-InP) and its effects on the barrier parameters and current transport phenomena in the Au/un-InP Schottky contact (SC). Using XRD and XPS, the structural and chemical features of MgO are assessed, confirming that the MgO was deposited on un-InP. The current-voltage (log(I)-V) features were measured for the SC and Au/MgO/un-InP metal/insulator/semiconductor (MIS)-type Schottky contact. The MIS contact revealed an excellent rectification behavior as compared to the SC. The calculated barrier height (Φb) was higher for the MIS contact (0.61 eV) than the SC (0.52 eV), which implies that the MgO interlayer influences the Φb of the SC. The Φb was also estimated using the Cheung's, Mikhelashvili and Norde procedures, the values are similar, indicating their stability and reliability. The acquired interface state density (NSS) of the MIS contact was less than the SC, proving that the MgO interlayer reduced the NSS. The ohmic behavior was observed in the lower bias region for the SC and MIS contacts, while the trap-free space-charge-limited current (SCLC) was noted in the moderate and upper bias regions of the MIS contact under forward bias. Poole-Frenkel emission (PFE) governs at a lower bias, while Schottky emission (SE) dominates at the upper bias of SC and MIS contacts under reverse bias. These findings demonstrate the potential application of MgO interlayer in advancing electronic devices.
这项研究探讨了未掺杂 InP（un-InP）上旋涂氧化镁（MgO）的结构和化学特性及其对金/未掺杂 InP 肖特基接触（SC）中的势垒参数和电流传输现象的影响。利用 XRD 和 XPS 评估了氧化镁的结构和化学特征，证实氧化镁沉积在未掺杂 InP 上。测量了SC和金/氧化镁/未铟磷金属/绝缘体/半导体（MIS）型肖特基触点的电流-电压（log(I)-V）特征。与 SC 相比，MIS 触点具有出色的整流性能。计算得出的 MIS 触点的势垒高度（Φb）（0.61 eV）高于 SC（0.52 eV），这意味着 MgO 中间层影响了 SC 的Φb。此外，还使用 Cheung's、Mikhelashvili 和 Norde 程序估算了 Φb 值，其值相近，表明其稳定性和可靠性。MIS 触点获得的界面态密度（NSS）小于 SC，证明氧化镁夹层降低了 NSS。在正向偏压下，SC 和 MIS 触点在低偏压区观察到欧姆行为，而 MIS 触点在中等偏压区和高偏压区观察到无阱空间电荷限制电流（SCLC）。在反向偏压下，普尔-弗伦克尔发射（PFE）在较低偏压下占主导地位，而肖特基发射（SE）则在 SC 和 MIS 触点的较高偏压下占主导地位。这些发现证明了氧化镁中间膜在先进电子器件中的潜在应用。
{"title":"Chemical and structural features of spin-coated magnesium oxide (MgO) and its impact on the barrier parameters and current conduction process of Au/undoped-InP Schottky contact as an interfacial layer","authors":"S. Sai Krupa , D. Surya Reddy , V. Rajagopal Reddy , Chel-Jong Choi","doi":"10.1016/j.ssc.2024.115757","DOIUrl":"10.1016/j.ssc.2024.115757","url":null,"abstract":"<div><div>This work examines the structural and chemical characteristics of spin-coated magnesium oxide (MgO) on undoped InP (un-InP) and its effects on the barrier parameters and current transport phenomena in the Au/un-InP Schottky contact (SC). Using XRD and XPS, the structural and chemical features of MgO are assessed, confirming that the MgO was deposited on un-InP. The current-voltage (log(I)-V) features were measured for the SC and Au/MgO/un-InP metal/insulator/semiconductor (MIS)-type Schottky contact. The MIS contact revealed an excellent rectification behavior as compared to the SC. The calculated barrier height (Φ<sub>b</sub>) was higher for the MIS contact (0.61 eV) than the SC (0.52 eV), which implies that the MgO interlayer influences the Φ<sub>b</sub> of the SC. The Φ<sub>b</sub> was also estimated using the Cheung's, Mikhelashvili and Norde procedures, the values are similar, indicating their stability and reliability. The acquired interface state density (N<sub>SS</sub>) of the MIS contact was less than the SC, proving that the MgO interlayer reduced the N<sub>SS</sub>. The ohmic behavior was observed in the lower bias region for the SC and MIS contacts, while the trap-free space-charge-limited current (SCLC) was noted in the moderate and upper bias regions of the MIS contact under forward bias. Poole-Frenkel emission (PFE) governs at a lower bias, while Schottky emission (SE) dominates at the upper bias of SC and MIS contacts under reverse bias. These findings demonstrate the potential application of MgO interlayer in advancing electronic devices.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"396 ","pages":"Article 115757"},"PeriodicalIF":2.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-12DOI: 10.1016/j.ssc.2024.115754
Shivani Gohri, Jaya Madan, Rahul Pandey
Low-cost materials are used in this work to make a triple-junction tandem solar cell (TSC). Two-step filtered spectrum and current matching techniques are used to design a perovskite-CIGS-SnS based TSC using a SCAPS-1D simulator. To design a TSC, the top cell (TC) is illuminated with a 1.5AM spectrum, and the unabsorbed spectrum of the TC is utilized for the middle cell (MC). Similarly, the unabsorbed spectrum of the MC is used to illuminate the bottom cell (BC). Additional merits of this work: the perovskite used is a two-dimensional Dion Jacobson (DJ) perovskite, which is more stable than conventional perovskites. The results show that current matching is obtained at active layer thickness (nm) of 365/600/100 for TC/MC/BC, respectively. The proposed solar cell shows a remarkable PV performance of 3.25 V VOC, 9.42 mA/cm2 JSC, 79.3 % FF and 24.27 % PCE.
{"title":"Spectral management and current matching optimization for high-efficiency perovskite-CIGS-SnS triple junction tandem solar cells","authors":"Shivani Gohri, Jaya Madan, Rahul Pandey","doi":"10.1016/j.ssc.2024.115754","DOIUrl":"10.1016/j.ssc.2024.115754","url":null,"abstract":"<div><div>Low-cost materials are used in this work to make a triple-junction tandem solar cell (TSC). Two-step filtered spectrum and current matching techniques are used to design a perovskite-CIGS-SnS based TSC using a SCAPS-1D simulator. To design a TSC, the top cell (TC) is illuminated with a 1.5AM spectrum, and the unabsorbed spectrum of the TC is utilized for the middle cell (MC). Similarly, the unabsorbed spectrum of the MC is used to illuminate the bottom cell (BC). Additional merits of this work: the perovskite used is a two-dimensional Dion Jacobson (DJ) perovskite, which is more stable than conventional perovskites. The results show that current matching is obtained at active layer thickness (nm) of 365/600/100 for TC/MC/BC, respectively. The proposed solar cell shows a remarkable PV performance of 3.25 V V<sub>OC</sub>, 9.42 mA/cm<sup>2</sup> J<sub>SC</sub>, 79.3 % FF and 24.27 % PCE.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"395 ","pages":"Article 115754"},"PeriodicalIF":2.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-12DOI: 10.1016/j.ssc.2024.115752
Zhenwu Zeng , Jiayu Wang , Can Tian , Fangfei Li , Tian Cui
The dense boron carbide (B-C) phases with diamond structure are predicted to be superhard, with hardness close to that of a cubic boron nitride (c-BN). At ambient conditions, graphite-like BC3 is well characterized, firstly reported by Kouvetakis et al. In this work, we have synthesized a new B-C phase from the graphite-like BC3 in a laser-heated diamond anvil cell. Interestingly, this phase could be recoverable to ambient pressure due to dynamic stabilities. The Raman spectrum and X-ray diffraction patterns give the possible structure of this new phase.
据预测，具有金刚石结构的致密碳化硼（B-C）相具有超硬特性，硬度接近立方氮化硼（c-BN）。在这项工作中，我们在激光加热的金刚石砧槽中从类石墨 BC3 合成了一种新的 B-C 相。有趣的是，由于动态稳定性，这种相可以在环境压力下恢复。拉曼光谱和 X 射线衍射图样给出了这种新相的可能结构。
{"title":"High pressure and high temperature synthesis of a new boron carbide phase","authors":"Zhenwu Zeng , Jiayu Wang , Can Tian , Fangfei Li , Tian Cui","doi":"10.1016/j.ssc.2024.115752","DOIUrl":"10.1016/j.ssc.2024.115752","url":null,"abstract":"<div><div>The dense boron carbide (B-C) phases with diamond structure are predicted to be superhard, with hardness close to that of a cubic boron nitride (c-BN). At ambient conditions, graphite-like BC<sub>3</sub> is well characterized, firstly reported by Kouvetakis et al. In this work, we have synthesized a new B-C phase from the graphite-like BC<sub>3</sub> in a laser-heated diamond anvil cell. Interestingly, this phase could be recoverable to ambient pressure due to dynamic stabilities. The Raman spectrum and X-ray diffraction patterns give the possible structure of this new phase.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"396 ","pages":"Article 115752"},"PeriodicalIF":2.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-08DOI: 10.1016/j.ssc.2024.115751
Xi Fu , Jian Lin , Guangyao Liang , Wenhu Liao , Xiaowu Li , Liming Li
As a nonlinear phenomenon, photogalvanic effect in low dimensional materials have attracted intensive attentions at recent years. In this paper, based on a typical two-dimensional pentagon material penta-PtN2 monolayer, we built a photodetector device which including the vacancy and substitution-doping situations, and studied their spin photocurrents generated by the photogalvanic effect, respectively. It has been found that the spin photocurrents in these PtN2-PhoDets exhibited the relations cos(2θ+θ0) on the polarization angle, and different photon energies can affect these relations. Moreover, since the symmetry of PtN2-PhoDets decrease from C2v to Cs when introducing the vacancy and substitution-doping, the strength of spin photocurrents slightly enlarged showing the enhancement of PGE. Furthermore, there exhibited very high spin polarizations, which were close to the 100 % full spin polarization at the Pt-Vacancy, Doping(N)-Pt and Doping(Pt)-N2 situations, and then pure spin current can form at these special situations. Additionally, the relative high extinction ratios show that the PtN2-PhoDets were high-sensitive. The findings indicated that the penta-PtN2 monolayer was of considerable significances on the practical applications in low-energy power optoelectronic and spintronic devices.
{"title":"Spin-dependent photogalvanic effect in the photodetector device based on penta-PtN2 monolayer","authors":"Xi Fu , Jian Lin , Guangyao Liang , Wenhu Liao , Xiaowu Li , Liming Li","doi":"10.1016/j.ssc.2024.115751","DOIUrl":"10.1016/j.ssc.2024.115751","url":null,"abstract":"<div><div>As a nonlinear phenomenon, photogalvanic effect in low dimensional materials have attracted intensive attentions at recent years. In this paper, based on a typical two-dimensional pentagon material penta-PtN<sub>2</sub> monolayer, we built a photodetector device which including the vacancy and substitution-doping situations, and studied their spin photocurrents generated by the photogalvanic effect, respectively. It has been found that the spin photocurrents in these PtN<sub>2</sub>-PhoDets exhibited the relations cos(2<em>θ</em>+<em>θ</em><sub>0</sub>) on the polarization angle, and different photon energies can affect these relations. Moreover, since the symmetry of PtN<sub>2</sub>-PhoDets decrease from <em>C</em><sub><em>2v</em></sub> to <em>C</em><sub><em>s</em></sub> when introducing the vacancy and substitution-doping, the strength of spin photocurrents slightly enlarged showing the enhancement of PGE. Furthermore, there exhibited very high spin polarizations, which were close to the 100 % full spin polarization at the Pt-Vacancy, Doping(N)-Pt and Doping(Pt)-N2 situations, and then pure spin current can form at these special situations. Additionally, the relative high extinction ratios show that the PtN<sub>2</sub>-PhoDets were high-sensitive. The findings indicated that the penta-PtN<sub>2</sub> monolayer was of considerable significances on the practical applications in low-energy power optoelectronic and spintronic devices.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"395 ","pages":"Article 115751"},"PeriodicalIF":2.1,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-08DOI: 10.1016/j.ssc.2024.115750
I.M. Saavedra Gaona , C.F. Camargo Castillo , J.E. Duarte , J. Roa-Rojas , D.A. Landínez Téllez , J. Munevar , C.A. Parra Vargas
The effect of the rare earth (RE) ion substitution on the structural, morphological, optical and magnetic properties of the Y1-xRExBaCuFeO5 (RE = Gd, Dy; x = 0.2, 0.4, 0.6, and 0.8) multiferroic compounds grown by the solid-state reaction is evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), dispersive X-ray spectroscopy (EDX), reflectance spectroscopy techniques diffuse (UV–vis–NIR) and vibrating sample magnetometry (VSM). The results indicate that the RE substitution led to growth of single-phase materials, with a tetragonal structure and P4mm symmetry. The morphological analysis shows the formation of polycrystalline materials composed of grains of various shapes and sizes. Furthermore, the compositional analysis reveals that the materials do not present elements other than those used in the synthesis. The band gap (Eg) is tuned from 0.88 to 0.90 eV upon RE substitution. The magnetization curves obtained in the Zero-Field-Cooled/Field-Cooled (ZFC-FC) modes between 50 and 390 K, reveal a paramagnetic behavior, which could be attributed to the dominance exerted by the magnetic moments of the Gd/Dy ions.
利用 X 射线衍射 (XRD)、扫描电子显微镜 (SEM)、色散 X 射线光谱 (EDX)，评估了稀土 (RE) 离子替代对固态反应生长的 Y1-xRExBaCuFeO5（RE = Gd、Dy；x = 0.2、0.4、0.6 和 0.8）的多铁化合物进行了评估，评估采用了 X 射线衍射 (XRD)、扫描电子显微镜 (SEM)、色散 X 射线光谱 (EDX)、漫反射光谱技术（UV-vis-NIR）和振动样品磁力计 (VSM)。结果表明，RE 替代导致了单相材料的生长，这种材料具有四方结构和 P4mm 对称性。形态分析表明形成了由各种形状和大小的晶粒组成的多晶材料。此外，成分分析表明，除合成过程中使用的元素外，材料中不存在其他元素。取代 RE 后，带隙（Eg）从 0.88 eV 调整到 0.90 eV。在 50 至 390 K 之间的零场冷却/场冷却（ZFC-FC）模式下获得的磁化曲线显示出顺磁性，这可能是由于 Gd/Dy 离子的磁矩占主导地位。
{"title":"Effect of rare earth doping on structural, morphological, optical, and magnetic properties of the Y1-x(Gd, Dy)xBaCuFeO5 (x = 0.2, 0.4, 0.6, and 0.8) ceramics","authors":"I.M. Saavedra Gaona , C.F. Camargo Castillo , J.E. Duarte , J. Roa-Rojas , D.A. Landínez Téllez , J. Munevar , C.A. Parra Vargas","doi":"10.1016/j.ssc.2024.115750","DOIUrl":"10.1016/j.ssc.2024.115750","url":null,"abstract":"<div><div>The effect of the rare earth (RE) ion substitution on the structural, morphological, optical and magnetic properties of the Y<sub>1-<em>x</em></sub>RE<sub><em>x</em></sub>BaCuFeO<sub>5</sub> (RE = Gd, Dy; <em>x</em> = 0.2, 0.4, 0.6, and 0.8) multiferroic compounds grown by the solid-state reaction is evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), dispersive X-ray spectroscopy (EDX), reflectance spectroscopy techniques diffuse (UV–vis–NIR) and vibrating sample magnetometry (VSM). The results indicate that the RE substitution led to growth of single-phase materials, with a tetragonal structure and <em>P</em>4<em>mm</em> symmetry. The morphological analysis shows the formation of polycrystalline materials composed of grains of various shapes and sizes. Furthermore, the compositional analysis reveals that the materials do not present elements other than those used in the synthesis. The band gap (E<sub><em>g</em></sub>) is tuned from 0.88 to 0.90 eV upon RE substitution. The magnetization curves obtained in the Zero-Field-Cooled/Field-Cooled (ZFC-FC) modes between 50 and 390 K, reveal a paramagnetic behavior, which could be attributed to the dominance exerted by the magnetic moments of the Gd/Dy ions.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"395 ","pages":"Article 115750"},"PeriodicalIF":2.1,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
The effect of an electric field on thermal and dielectric properties as well as electrocaloric response in the ferroelectric NH4HSeO4 has been studied using a universal multifunctional adiabatic calorimeter. The phase transition temperature between the ferroelectric and incommensurate phases is found to be highly sensitive to the electric field, dT2/dE ≈ 1.6 K/(kV/cm), at a low electric field strength. The intensive electrocaloric effect at E = 1.35 kV/cm observed by direct measurements, ΔTAD ≈ 0.045 K, as well as determined indirectly by analyzing the entropy-temperature-electric field phase diagram, ΔTAD ≈ 0.03 K, is quite large compared to the effects in other ferroelectrics.
{"title":"High sensitivity to the electric field of both the phase transition temperature and the electrocaloric effect in ferroelectric NH4HSeO4","authors":"V.S. Bondarev , E.A. Mikhaleva , M.V. Gorev , I.N. Flerov","doi":"10.1016/j.ssc.2024.115747","DOIUrl":"10.1016/j.ssc.2024.115747","url":null,"abstract":"<div><div>The effect of an electric field on thermal and dielectric properties as well as electrocaloric response in the ferroelectric NH<sub>4</sub>HSeO<sub>4</sub> has been studied using a universal multifunctional adiabatic calorimeter. The phase transition temperature between the ferroelectric and incommensurate phases is found to be highly sensitive to the electric field, d<em>T</em><sub>2</sub>/d<em>E</em> ≈ 1.6 K/(kV/cm), at a low electric field strength. The intensive electrocaloric effect at <em>E</em> = 1.35 kV/cm observed by direct measurements, Δ<em>T</em><sub>AD</sub> ≈ 0.045 K, as well as determined indirectly by analyzing the entropy-temperature-electric field phase diagram, Δ<em>T</em><sub>AD</sub> ≈ 0.03 K, is quite large compared to the effects in other ferroelectrics.</div></div>","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"395 ","pages":"Article 115747"},"PeriodicalIF":2.1,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Pub Date : 2024-11-04DOI: 10.1016/j.ssc.2024.115744
Nzar Rauf Abdullah , Shaida Anwer Kakil , Vidar Gudmundsson
<div><div>Density functional theory is employed to study the novel properties of B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer to gain a deeper understanding of variation of electronic, thermal, and optical characteristics arising due to buckling effects. The band structure analysis reveals an energy gap reduction of the buckled B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer, causing a displacement of the band gap from the visible to the infrared range. Moreover, the buckling controls the location of the initially, and finally, direct band gap moving it from the K to the <span><math><mi>Γ</mi></math></span> point in the B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer. The phonon band structure calculations indicate that buckled B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayers are dynamically stable, while ab-initio molecular dynamics simulations, AIMD, evaluate and confirm the thermal stability of both flat and buckled B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayers. The buckling phenomenon at low temperatures has no a significant impact on the heat capacity contrary to what happens in the high temperature limit. The optical characteristics of the B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer, including refractive index, optical conductivity, static dielectric function, and plasmon frequency, are evaluated at different levels of the buckling parameter. The static dielectric function and plasmon frequency are enhanced with the buckling due to the screening of the electron–electron interactions, affecting the collective oscillations. Enhanced screening gives rise higher plasmon frequencies. Tuning the buckling parameter illustrates the significance of buckling as an alternative mechanism for adjusting the performance of B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow
{"title":"Buckling-induced variations in electronic, thermal, and optical properties of B3C2N3 monolayer: DFT and AIMD computational approaches","authors":"Nzar Rauf Abdullah , Shaida Anwer Kakil , Vidar Gudmundsson","doi":"10.1016/j.ssc.2024.115744","DOIUrl":"10.1016/j.ssc.2024.115744","url":null,"abstract":"<div><div>Density functional theory is employed to study the novel properties of B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer to gain a deeper understanding of variation of electronic, thermal, and optical characteristics arising due to buckling effects. The band structure analysis reveals an energy gap reduction of the buckled B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer, causing a displacement of the band gap from the visible to the infrared range. Moreover, the buckling controls the location of the initially, and finally, direct band gap moving it from the K to the <span><math><mi>Γ</mi></math></span> point in the B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer. The phonon band structure calculations indicate that buckled B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayers are dynamically stable, while ab-initio molecular dynamics simulations, AIMD, evaluate and confirm the thermal stability of both flat and buckled B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayers. The buckling phenomenon at low temperatures has no a significant impact on the heat capacity contrary to what happens in the high temperature limit. The optical characteristics of the B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>N<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> monolayer, including refractive index, optical conductivity, static dielectric function, and plasmon frequency, are evaluated at different levels of the buckling parameter. The static dielectric function and plasmon frequency are enhanced with the buckling due to the screening of the electron–electron interactions, affecting the collective oscillations. Enhanced screening gives rise higher plasmon frequencies. Tuning the buckling parameter illustrates the significance of buckling as an alternative mechanism for adjusting the performance of B<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>C<span><math><msub><mrow","PeriodicalId":430,"journal":{"name":"Solid State Communications","volume":"395 ","pages":"Article 115744"},"PeriodicalIF":2.1,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
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