Journal of Superconductivity and Novel Magnetism最新文献_第8页

Spin Crossover of Local Copper-Oxygen States in the HTSC Cuprate La(_{2-x})Sr(_x)CuO(_4) Under the c-Axis Pressure c轴压力下HTSC Cuprate La (_{2-x}) Sr (_x) CuO (_4)中局部铜氧态的自旋交叉

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-08 DOI: 10.1007/s10948-025-06928-5

Ilya Makarov, Sergei Ovchinnikov

{"title":"Spin Crossover of Local Copper-Oxygen States in the HTSC Cuprate La(_{2-x})Sr(_x)CuO(_4) Under the c-Axis Pressure","authors":"Ilya Makarov, Sergei Ovchinnikov","doi":"10.1007/s10948-025-06928-5","DOIUrl":"10.1007/s10948-025-06928-5","url":null,"abstract":"<div>In this work, the change in the energy and structure of local many-particle states of HTSC cuprate La(_{2-x})Sr(_x)CuO(_4) under the uniaxial compression along the c-axis is studied. Local copper-oxygen states are obtained using exact diagonalization of the CuO(_6) octahedron as a part of the GTB method for the five-band p-d model. The dependence of interatomic distances on the c-axis compression is calculated according to Hooke’s law using elastic constants; the influence of interatomic distances on the on-site energies and hopping integrals is obtained using linear extrapolation of the results of ab initio calculations and the theory of MT-orbitals, respectively. The c-axis compression leads to a decrease in the energy of hole states with the nature of the (a_{1g}) symmetry orbitals. At a pressure value of (P_{c1}^{left( c right) } = 11.8) GPa, a spin crossover between the Zhang-Rice singlet and the triplet state (B_1) occurs. At higher pressures, a second spin crossover between two-hole states and a crossover of single-hole states with different orbital compositions were also detected. Taking into account the competition of various local states with changing the value of uniaxial compression, the effective five-band Hubbard model is formulated to describe the electronic structure of quasiparticle excitations.</div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361854","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}

引用次数: 0

Observation of Giant Zero-Field Cooled Spontaneous Exchange Bias Effect in La2FeCoO6 Double Perovskite Ceramic La2FeCoO6双钙钛矿陶瓷巨零场冷却自发交换偏置效应的观察

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-07 DOI: 10.1007/s10948-025-06927-6

Lav Kush, Sanjay Srivastava

{"title":"Observation of Giant Zero-Field Cooled Spontaneous Exchange Bias Effect in La2FeCoO6 Double Perovskite Ceramic","authors":"Lav Kush, Sanjay Srivastava","doi":"10.1007/s10948-025-06927-6","DOIUrl":"10.1007/s10948-025-06927-6","url":null,"abstract":"<div>The La2FeCoO6 ceramic was synthesized via the sol–gel route, and their temperature-dependent exchange bias (EB) effects have been analyzed at different magnetic fields. XRD investigation reveals that at a lower temperature, the monoclinic structure with the P21/n space group was maintained, whereas, from room temperature to 450 K, the rhombohedral structure with the R3c space group was noticed. The tolerance factor suggested the presence of distortion, and the XPS analysis of Fe and Co confirms the defect sites in La2FeCoO6. Hence, the variety of magnetic phases formed during the FC and ZFC processes resulted in unidirectional anisotropy. Negative field cooling magnetization was observed in M-T measurements, and ferromagnetic clusters were detected at room temperature M-H measurements. Negative EB fields and upward shifts in hysteresis were observed at low temperatures. The hysteresis and EB fields changed below the Neel transition, with a transition from positive to negative EB observed with increasing magnetic field and temperature. The observed EB was attributed to the pinning effect of surface spins in interfacial frozen glassy states at the interface of large ferrimagnetic grains.</div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361648","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}

引用次数: 0

Thermal Gradient Powering Spin Current in Quantum Dot-Magnetic Insulators Hybrid 热梯度驱动量子点-磁绝缘体混合自旋电流

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-07 DOI: 10.1007/s10948-025-06921-y

Emil Siuda, Piotr Trocha

{"title":"Thermal Gradient Powering Spin Current in Quantum Dot-Magnetic Insulators Hybrid","authors":"Emil Siuda, Piotr Trocha","doi":"10.1007/s10948-025-06921-y","DOIUrl":"10.1007/s10948-025-06921-y","url":null,"abstract":"<div>The growing energy consumption of the computational sector worldwide necessitates the search for sustainable methods of powering and performing calculations. The fast-emerging field of spin caloritronics offers a promising solution by combining the advantages of performing computations on spins instead of charges and driving these computations through temperature differences rather than voltage. Among the various approaches, spin waves and their quanta of excitations, known as magnons, are considered promising carriers of spin-encoded information. In this article, we examine the magnon current generated in a system composed of a magnetic insulator/quantum dot/magnetic insulator, driven by a small temperature difference applied between the two insulators. By expanding the magnon current in terms of the applied temperature bias, we analyze the contributions of successive terms up to the third order of the temperature difference. Each term exhibits a similar structure, consisting of a driving-like and a damping-like component. The driving-like term is dependent on the coupling strength between the quantum dot and the electrodes. We explicitly show that the second-order term of the magnon current vanishes when the couplings of the quantum dot to the magnetic insulators are equal. Overall, the first two terms are sufficient to capture the behavior of the magnon current across the full range of temperature differences. For extreme values of the temperature gradient, the approximate results align with the exact ones only when there is significant asymmetry in the coupling strengths. Finally, we demonstrate that the system can function as a spin diode, capable of rectifying the magnon current when the temperature bias is reversed.</div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143362058","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}

引用次数: 0

Room-Temperature Ferromagnetism in ZnTe Nanosheet Doped by Transition Metal Atom 掺杂过渡金属原子的 ZnTe 纳米片的室温铁磁性

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-06 DOI: 10.1007/s10948-025-06920-z

Narmin A. Ismayilova

{"title":"Room-Temperature Ferromagnetism in ZnTe Nanosheet Doped by Transition Metal Atom","authors":"Narmin A. Ismayilova","doi":"10.1007/s10948-025-06920-z","DOIUrl":"10.1007/s10948-025-06920-z","url":null,"abstract":"<div>To investigate the potential functionalities of transition metal atom (V, Cr, Mn, Fe, Co, and Cu)-doped ZnTe nanosheets in nanoscale science and spintronic applications, we conducted spin-polarized density functional theory calculations. This study focused on doping at various concentrations of transition metal atoms, with the Zn edge which was the substitution position. The pristine ZnTe nanosheet is intrinsically nonmagnetic; however, the introduction of transition metal atoms induces spontaneous spin polarization, resulting in a significant magnetic moment. Electronic structure calculations reveal distinct conducting behaviors—semiconducting and half-metallic—depending on the concentration of the dopant atoms. Furthermore, the calculated Curie temperature, obtained through mean-field approximation, indicates values exceeding room temperature for all concentrations of V, Cr, Fe, and Cu, with an increasing trend as the concentration of transition metal atoms rises. These findings suggest that Cr-, Fe-, and Cu-doped ZnTe nanosheets may be good candidates for spintronic applications due to their ferromagnetism and high Curie temperatures.</div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361944","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}

引用次数: 0

Manipulating the Magnetic Characteristics of Defective SrTiO3 (001) Surfaces Through O2 Adsorption: An Investigation via Hybrid Functional Calculations 通过氧吸附操纵缺陷SrTiO3（001）表面的磁特性：基于混合泛函数计算的研究

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-06 DOI: 10.1007/s10948-025-06926-7

Lihui Sun, Xinhui Lv, Yi Xu, Lin Xue, Yongjia Zhang

{"title":"Manipulating the Magnetic Characteristics of Defective SrTiO3 (001) Surfaces Through O2 Adsorption: An Investigation via Hybrid Functional Calculations","authors":"Lihui Sun, Xinhui Lv, Yi Xu, Lin Xue, Yongjia Zhang","doi":"10.1007/s10948-025-06926-7","DOIUrl":"10.1007/s10948-025-06926-7","url":null,"abstract":"<div>The electronic and magnetic properties of defective SrTiO3 (001) surfaces were examined through hybrid functional calculations, focusing on the impact of O2 adsorption. Among the various vacancy types considered—oxygen vacancy (VO), titanium vacancy (VTi), strontium vacancy (VSr), VTi + VO complex (VTi-O), and VSr + VO complex (VSr-O)—only VO, VTi, and VTi-O exhibit magnetic moments. At low O2 coverage, the adsorption of a single O2 molecule onto each defective surface results in a reduction of the magnetic moments for surfaces with VO, VTi, or VTi-O, potentially decreasing to zero. In contrast, the magnetic moment of surfaces with VSr-O increases from zero to 2 μB. Upon the addition of a second O2 molecule at high O2 coverage, the magnetic moments of surfaces with VO and VTi are significantly enhanced, attributed to the polarization of the p electrons of the two adsorbed O2 molecules. Surfaces with VTi-O or VSr-O complex defects do not adsorb additional O2 molecules, and surfaces with VSr are unable to adsorb O2 molecules. The variation in magnetic moments for the defective surfaces is correlated with the number of electrons acquired by the adsorbed O2 molecules.</div>","PeriodicalId":669,"journal":{"name":"Journal of Superconductivity and Novel Magnetism","volume":"38 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361945","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}

引用次数: 0

Geometric Phase in Kitaev Quantum Spin Liquid 基塔耶夫量子自旋液体中的几何相位

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-05 DOI: 10.1007/s10948-025-06919-6

Zheng-Chuan Wang

引用次数: 0

Probing Magnetic Characteristics of (Co_{60}Fe_{40}) Films Prepared by Pulsed Laser Deposition 脉冲激光沉积(Co_{60}Fe_{40})薄膜的探测磁特性

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-05 DOI: 10.1007/s10948-025-06922-x

Khalil El Achi, Samih Isber, Malek Tabbal, Mohammad Haidar

引用次数: 0

Impact of Cr Insertion Layer on Spin Transport Properties in Co2FeAl/Ta System Cr插入层对Co2FeAl/Ta体系自旋输运特性的影响

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-02-01 DOI: 10.1007/s10948-025-06914-x

Rohiteswar Mondal, Vidya Alman, Arabinda Haldar, Chandrasekhar Murapaka

引用次数: 0

Current-Phase Relation for Transparent Superconducting Junctions 透明超导结的电流-相关系

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-01-30 DOI: 10.1007/s10948-025-06916-9

Artem V. Galaktionov, Andrei D. Zaikin

引用次数: 0

Memory Function of a Three-Dimensional Holstein-Like System 三维类荷尔斯坦系统的记忆函数

IF 1.6 4区物理与天体物理

Journal of Superconductivity and Novel Magnetism Pub Date : 2025-01-30 DOI: 10.1007/s10948-025-06911-0

Zoran Rukelj, Danko Radić, Ivan Kupčić

引用次数: 0