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Spin and valley half metal induced by staggered potential and magnetization in silicene 被引量:2
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作者 汪萨克 田宏玉 +1 位作者 杨永宏 汪军 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期379-383,共5页
We investigate the electron transport in silicene with both staggered electric potential and magnetization; the latter comes from the magnetic proximity effect by depositing silicene on a magnetic insulator. It is sho... We investigate the electron transport in silicene with both staggered electric potential and magnetization; the latter comes from the magnetic proximity effect by depositing silicene on a magnetic insulator. It is shown that the silicene could be a spin and valley half metal under appropriate parameters when the spin–orbit interaction is considered; further, the filtered spin and valley could be controlled by modulating the staggered potential or magnetization. It is also found that in the spin-valve structure of silicene, not only can the antiparallel magnetization configuration significantly reduce the valve-structure conductance, but the reversing staggered electric potential can cause a high-performance magnetoresistance due to the spin and valley blocking effects. Our findings show that the silicene might be an ideal basis for the spin and valley filter analyzer devices. 展开更多
关键词 SILICENE spin–orbit interaction spin and valley half metal spin and valley blocking effect
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First-Principles Calculation for the Half Metallic Properties of La2NbMnO6
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作者 Ning-Ning Zu Rui Li +1 位作者 Ya-Hui Zheng Lin Chen 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期70-73,共4页
La2 VMnO6 is measured to be insulating and ferrimagnetic experimentally. In this study, by substituting V with Nb, La2NbMnO6 is investigated using the density functional theory. The calculated results indicate that La... La2 VMnO6 is measured to be insulating and ferrimagnetic experimentally. In this study, by substituting V with Nb, La2NbMnO6 is investigated using the density functional theory. The calculated results indicate that La2 NbMnO6 is also ferrimagnetic and exhibits the half metallic properties due to the strong electron correlation of Mn. The valence states of Nb and Mn are assigned to be 4-4 and +2 in La2NbMn06, respectively, which are different from V3+/Mn3+ in La2 VMnO6. 展开更多
关键词 GGA MN First-Principles Calculation for the half metallic Properties of La2NbMnO6 LA
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Half-metallic ferromagneticWeyl fermions related to dynamic correlations in the zinc-blende compound VAs
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作者 Xianyong Ding Haoran Wei +3 位作者 Ruixiang Zhu Xiaoliang Xiao Xiaozhi Wu Rui Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期528-533,共6页
The realization of 100%polarized topologicalWeyl fermions in half-metallic ferromagnets is of particular importance for fundamental research and spintronic applications.Here,we theoretically investigate the electronic... The realization of 100%polarized topologicalWeyl fermions in half-metallic ferromagnets is of particular importance for fundamental research and spintronic applications.Here,we theoretically investigate the electronic and topological properties of the zinc-blende compound VAs,which was deemed as a half-metallic ferromagnet related to dynamic correlations.Based on the combination of density functional theory and dynamical mean field theory,we uncover that the half-metallic ferromagnet VAs exhibits attractive Weyl semimetallic behaviors which are very close to the Fermi level in the DFT+U regime with effect U values ranging from 1.5 eV to 2.5 eV.Meanwhile,we also investigate the magnetization-dependent topological properties;the results show that the change of magnetization directions only slightly affects the positions of Weyl points,which is attributed to the weak spin–orbital coupling effects.The topological surface states of VAs projected on semi-infinite(001)and(111)surfaces are investigated.The Fermi arcs of all Weyl points are clearly visible on the projected Fermi surfaces.Our findings suggest that VAs is a fully spin-polarized Weyl semimetal with many-body correlated effects in the effective U values range from 1.5 eV to 2.5 eV. 展开更多
关键词 density functional theory Weyl semimetal dynamical mean field theory half metallic ferromagnet
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The atlas of ferroicity in two-dimensional MGeX_(3) family:Room-temperature ferromagnetic half metals and unexpected ferroelectricity and ferroelasticity 被引量:1
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作者 Kuan-Rong Hao Xing-Yu Ma +3 位作者 Hou-Yi Lyu Zhen-Gang Zhu Qing-Bo Yan Gang Su 《Nano Research》 SCIE EI CSCD 2021年第12期4732-4739,共8页
Two-dimensional(2D)ferromagnetic and ferroelectric materials attract unprecedented attention due to the spontaneous-symmetry-breaking induced novel properties and multifarious potential applications.Here we systematic... Two-dimensional(2D)ferromagnetic and ferroelectric materials attract unprecedented attention due to the spontaneous-symmetry-breaking induced novel properties and multifarious potential applications.Here we systematically investigate a large family(148)of 2D MGeX3(M=metal elements,X=O/S/Se/Te)by means of the high-throughput first-principles calculations,and focus on their possible ferroic properties including ferromagnetism,ferroelectricity,and ferroelasticity.We discover eight stable 2D ferromagnets including five semiconductors and three half-metals,212D antiferromagnets,and 11 stable 2D ferroelectric semiconductors including two multiferroic materials.Particularly,MnGeSe3 and MnGeTe3 are predicted to be room-temperature 2D ferromagnetic half metals with Tc of 490 and 308 K,respectively.It is probably for the first time that ferroelectricity is uncovered in 2D MGeX3 family,which derives from the spontaneous symmetry breaking induced by unexpected displacements of Ge-Ge atomic pairs,and we also reveal that the electric polarizations are in proportion to the ratio of electronegativity of X and M atoms,and IVB group metal elements are highly favored for 2D ferroelectricity.Magnetic tunnel junction and water-splitting photocatalyst based on 2D ferroic MGeX3 are proposed as examples of wide potential applications.The atlas of ferroicity in 2D MGeX3 materials will spur great interest in experimental studies and would lead to diverse applications. 展开更多
关键词 two-dimensional materials ferroicity FERROELECTRICITY FERROELASTICITY ferromagnetic half metal
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Structural Stability and Half Metallic Features of Zn_(0.5)Cr_(0.5)S under Pressure
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作者 Yuhong Huang Wanqi Jie +1 位作者 Yan Zhou Gangqiang Zha 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2014年第3期234-238,共5页
Spin-polarized first-principle was performed to study the structural stability and the electronic states of Cr doped ZnS with the Cr component of 50% in zincblende (ZB), wurtzite (W) and rocksalt (RS) structures... Spin-polarized first-principle was performed to study the structural stability and the electronic states of Cr doped ZnS with the Cr component of 50% in zincblende (ZB), wurtzite (W) and rocksalt (RS) structures under pressure. The results show that the zincblende and wurtzite structures become unstable under low pressures of about 4.68 and 9.61 GPa, respectively, but the rocksalt structure can be maintained up to an extremely high pressure of about 32.92 GPa. Both zincblende and wurtzite Zno.sCro.5S display half metallic features under pressure, while rocksalt Zno.sCro.sS exhibits metallic feature. The half metallic features can be ascribed to the stronger interactions between S-3p and Cr-3d states and the metallic feature is due to the higher crystal symmetry of rocksalt Zn0.5Cr0.5S. These results can provide helpful guidance for Cr doped ZnS to be used in spintronic devices. 展开更多
关键词 Structural stability half metallic features Electronic properties Zn0.5Cr0.5S PRESSURE
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Hydroxylation-induced half-metallicity in graphitic ZnO sheet
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作者 张俊 《Journal of Chongqing University》 CAS 2012年第3期127-133,共7页
The structural, electronic and magnetic properties of the hydroxylated graphitic Zinc oxide (ZnO) sheet were studied using the density functional theory. We found that the hydroxylation can induce a magnetic moment of... The structural, electronic and magnetic properties of the hydroxylated graphitic Zinc oxide (ZnO) sheet were studied using the density functional theory. We found that the hydroxylation can induce a magnetic moment of 1.0 μB per unit cell and turn graphitic ZnO sheet from semiconductor into half metal for the three studied hydroxylated configurations with a half-metal gap up to 0.60 eV. The relative stability of each situation was also discussed and the structure for hydroxyl absorbed above the hexagonal ring of ZnO sheet was the most steady. The prominent electronic and magnetic properties may endow 2D ZnO sheet great opportunity in future spintronics. 展开更多
关键词 density functional theory HYDROXYLATION half metallicity graphitic ZnO sheet
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Electronic and mechanical properties of half-metallic half-Heusler compounds CoCrZ(Z=S, Se, and Te) 被引量:1
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作者 黄海铭 张传坤 +3 位作者 贺泽东 张俊 杨俊涛 罗时军 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期501-507,共7页
The electronic structures, magnetic properties, half-metallicity, and mechanical properties of half-Heulser compounds CoCrZ (Z = S, Se, and Te) were investigated using first-principles calculations within generalize... The electronic structures, magnetic properties, half-metallicity, and mechanical properties of half-Heulser compounds CoCrZ (Z = S, Se, and Te) were investigated using first-principles calculations within generalized gradient approximation based on the density function theory. The half-Heusler compounds show half-metallic properties with a half-metallic gap of 0.15 eV for CoCrS, 0.10 eV for CoCrSe, and 0.31 eV for CoCrTe at equilibrium lattice constant, respectively. The total magnetic moments are 3.00/-tB per formula unit, which agrees well with the Slater-Pauling rule. The half-metallicity, elastic constants, bulk modulus, shear modulus, Pough's ratio, Frantesvich ratio, Young's modulus, Poisson's ratio, and Debye temperature at equilibrium lattice constant and versus lattice constants are reported for the first time. The results indicate that the half-Heulser compounds CoCrZ (Z = S, Se, and Te) maintain the perfect half-metallic and mechanical stability within the lattice constants range of 5.18-5.43 A for CoCrS, 5.09-5.61 A for CoCrSe, and 5.17-6.42 A for CoCrTe, respectively. 展开更多
关键词 half-Heusler half-metalLICITY elastic constants FIRST-PRINCIPLES
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Half-metallic ferromagnetism in C-doped zinc-blende ZnO: A first-principles study 被引量:1
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作者 但旭 姚凯伦 +1 位作者 高国营 马国强 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期467-470,共4页
We perform a first-principles study of electronic structure and magnetism of C-doped zinc-blende ZnO using the full-potential linearized augmented plane wave method. Results show that C-doped zinc-blende ZnO exhibits ... We perform a first-principles study of electronic structure and magnetism of C-doped zinc-blende ZnO using the full-potential linearized augmented plane wave method. Results show that C-doped zinc-blende ZnO exhibits half-metallic ferromagnetism with a stable ferromagnetic ground state. The calculated magnetic moment of the 32-atom supercell containing one C dopant is 2.00 μ B , and the C dopant contributes most. The calculated low formation energy suggests that C-doped zinc-blende ZnO is energetically stable. The hole-mediated double exchange mechanism can be used to explain the ferromagnetism in C-doped zinc-blende ZnO. 展开更多
关键词 half-metallic ferromagnetism FIRST-PRINCIPLES electronic structure
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Magnetic properties of several potential rocksalt half-metallic ferromagnets based on the first-principles calculations 被引量:1
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作者 刘俊 詹瑞 +1 位作者 李丽 董会宁 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期351-355,共5页
Several rocksalt Sr4X3N (X = O, S, Se, and Te) are predicted to be potential half-metallic ferromagnets free of transition-metal and rare-earth elements by performing the first-principles calculations. Then their ma... Several rocksalt Sr4X3N (X = O, S, Se, and Te) are predicted to be potential half-metallic ferromagnets free of transition-metal and rare-earth elements by performing the first-principles calculations. Then their magnetic properties, such as the half metallicity and the crystal-cell magnetic moments are investigated. The Sr4X3N possibly have higher Curie temperatures and have more stable half metallicity than the Sr4X3C. Their crystal-cell magnetic moments are all 1.00 μB. The crystal-cell magnetic moments and the half metallicity arise mainly from the N ions. The main mechanism is the strong covalent interaction leading to the sp2 hybridized orbitals in the Sr4X3N. Then two Sr-5s and three N-2p electrons enter into three sp2 hybridized orbitals. Among these five electrons, four electrons are paired and one is unpaired, so there are three spin-up electrons and two spin-down electrons in these sp2 hybridized orbitals. 展开更多
关键词 half-metallic ferromagnets first-principles calculations crystal-cell magnetic moments
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Effect of local atomic disorder on the half-metallicity of full-Heusler Co_2FeSi alloy:a first-principles study 被引量:1
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作者 李冠男 金迎九 李在一 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期485-491,共7页
This paper investigates the effect of atomic disorder on the electronic structure, magnetism, and half-metallicity of full-Heusler Co2FeSi alloy by using the full-potential linearized augmented plane wave method withi... This paper investigates the effect of atomic disorder on the electronic structure, magnetism, and half-metallicity of full-Heusler Co2FeSi alloy by using the full-potential linearized augmented plane wave method within the generalized gradient approximation (GGA) and GGA-kU schemes. It considers three types of atomic disorders in Co2FeSi alloy: the Co-Fe, Co-Si, and Fe-Si disorders. Total energy calculations show that of the three types of disorders, the Fe-Si disorder is more likely to occur. It finds that for the Co Si disorder, additional states appear in the minority band-gap at the EF and the half-metallcity is substantially destroyed, regardless of the disorder level. On the other hand, the Co-Fe and Fe-Si disorders have little effect on the half-metallicity at a low disorder level. When increasing the disorder levels, the half-metallcity is destroyed at about 9 % of the Co-Fe disorder level, while that stays at 25 % of the Fe-Si disorder level. 展开更多
关键词 half-metalLICITY full-Heusler alloy electronic structure full-potential linearized augmented plane wave method
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Theoretical Prediction of the Intrinsic Half-metallicity in One-dimensional Cr2NO2 Nanoribbons 被引量:1
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作者 王果 廖奕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第9期1544-1551,共8页
One-dimensional Cr2NO2 nanoribbons cut from the oxygen-passivated Cr2NO2 MXene were investigated by using density functional theory. The wide nanoribbons have ferromagnetic ground states and are intrinsic half-metals,... One-dimensional Cr2NO2 nanoribbons cut from the oxygen-passivated Cr2NO2 MXene were investigated by using density functional theory. The wide nanoribbons have ferromagnetic ground states and are intrinsic half-metals, independent of their chirality. The half-metallic band gaps of wide nanoribbons are larger than 1 eV, which are large enough for avoiding thermally activated spin flip. The magnetism does not rely on the edge states but originates from all the Cr atoms. Furthermore, the half-metallicity is still robust in an electronic device even if the bias is up to 1 V. Therefore, one-dimensional Cr2NO2 nanoribbons are good candidates for spintronics. 展开更多
关键词 Cr2NO2 nanoribbon intrinsic half-metallicity density functional theory
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Investigations of the half-metallic behavior and the magnetic and thermodynamic properties of half-Heusler CoMnTe and RuMnTe compounds: A first-principles study
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作者 T.Djaafri A.Djaafri +5 位作者 A.Elias G.Murtaza R.Khenata R.Ahmed S.Bin Omran D.Rached 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期444-451,共8页
First-principles spin-polarized density functional theory (DFT) investigations of the structural, electronic, magnetic, and thermodynamics characteristics of the half-Heusler, CoMnTe and RuMnTe compounds are carried... First-principles spin-polarized density functional theory (DFT) investigations of the structural, electronic, magnetic, and thermodynamics characteristics of the half-Heusler, CoMnTe and RuMnTe compounds are carried out. Calculations are accomplished within a state of the art full-potential (FP) linearized (L) augmented plane wave plus a local orbital (APW + lo) computational approach framed within DFT. The generalized gradient approximation (GGA) parameterized by Perdew, Burke, and Ernzerhof (PBE) is implemented as an exchange correlation functional as a part of the total energy calculation. From the analysis of the calculated electronic band structure as well as the density of states for both compounds, a strong hybridization between d states of the higher valent transition metal (TM) atoms (Co, Ru) and lower valent TM atoms of (Mn) is observed. Furthermore, total and partial density of states (PDOS) of the ground state and the results of spin magnetic moments reveal that these compounds are both stable and ideal half-metallic ferromagnetic. The effects of the unit cell volume on the magnetic properties and half-metaliicity are crucial. It is worth noting that our computed results of the total spin magnetic moments, for CoMnTe equal to 4 ~tB and 3 p-B per unit cell for RuMnTe, nicely follow the rule μ2tot = Zt - 18. Using the quasi-harmonic Debye model, which considers the phononic effects, the effecs of pressure P and temperature T on the lattice parameter, bulk modulus, thermal expansion coefficient, Debye temperature, and heat capacity for these compounds are investigated for the first time. 展开更多
关键词 half-Heusler alloys half-metallic behavior MAGNETISM thermodynamic properties first principlesmethods
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Theoretical prediction of half-metallicity of the encapsulated zigzag single walled carbon nanotube by NO,O_2 and NO_2 molecules
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作者 王晴 赵景祥 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第4期99-103,共5页
Finding half-metallic behavior in one-dimensional structure is a challenge for technological applications at the nanometer scale.In the present work,the investigation was performed on the structural,electronic,and mag... Finding half-metallic behavior in one-dimensional structure is a challenge for technological applications at the nanometer scale.In the present work,the investigation was performed on the structural,electronic,and magnetic properties of encapsulated zigzag carbon nanotube (CNT) with various sizes by the NO,NO2,and O2 molecules using spin-polarized density functional theory (DFT).It was found that the encapsulations of the three molecules inside the CNT are energetically favorable.The calculated adsorption energies are strongly dependent on the tube diameter and the orientation between the encapsulated molecules and tube axis,while the structures of both CNTs and encapsulated molecules are nearly unchanged.Interestingly,the encapsulated CNTs by the three molecules exhibit half-metallicty in terms of the opposite local gating effect of the spin states. 展开更多
关键词 Carbon nanotube ENCAPSULATION half-metalLICITY DFT
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First principles study on d^0 half-metallic properties of full-Heusler compounds RbCaX_2(X=C,N,and O)
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作者 高永春 王啸天 Habib Rozale 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期494-499,共6页
A first-principles approach is employed to study the structural, electronic, and magnetic properties of RbCaX2 (X = C, N, and O) full-Heusler compounds. It is observed that RbCaN2 and RbCaO2 are new do half-metals w... A first-principles approach is employed to study the structural, electronic, and magnetic properties of RbCaX2 (X = C, N, and O) full-Heusler compounds. It is observed that RbCaN2 and RbCaO2 are new do half-metals with an integer magnetic moment of 3 μB and 1 μB in their ferrimagnetic ground states, respectively, while RbCaC2 is a common metallic compound. Analysis of the density of states of these compounds indicates that the magnetic moment and furthermore, the half-metallicity primarily originate from the spin-polarization of the p-like states of N and O atoms. The half-metallic (HM) gaps of RbCaN2 and RbCaO2 are notably large; thus, the half-metallicity is robust against lattice distortion. Such materials are suitable to be grown on various semiconductor substrates. In addition, for RbCaN2 and RbCaO2, four possible terminations of the surface are also calculated. 展开更多
关键词 d0 half-metallicity electronic structure full-Heusler compound
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Spin-flip process through double quantum dots coupled to two half-metallic ferromagnetic leads
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作者 闫从华 吴绍全 +1 位作者 黄睿 孙威立 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期296-302,共7页
We investigate the spin-flip process through double quantum dots coupled to two half-metallic ferromagnetic leads in series. By means of the slave-boson mean-field approximation, we calculate the density of states in ... We investigate the spin-flip process through double quantum dots coupled to two half-metallic ferromagnetic leads in series. By means of the slave-boson mean-field approximation, we calculate the density of states in the Kondo regime for two different configurations of the leads. It is found that the transport shows some remarkable properties depending on the spin-flip strength. These effects may be useful in exploiting the role of electronic correlation in spintronics. 展开更多
关键词 SPIN-FLIP double quantum dots half-metallic ferromagnetic leads
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First-Principles Calculations on the Half-Metallicity of Rock-Salt Ferromagnetic FeO
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作者 Jun Liu Xiaolan Yang Wei Kang 《Journal of Materials Science and Chemical Engineering》 2015年第9期1-7,共7页
The geometrical structure of ferromagnetic FeO is optimized. Its electric and magnetic properties such as the half-metallicity, the conductivity and the magnetic moment distribution are investigated by performing firs... The geometrical structure of ferromagnetic FeO is optimized. Its electric and magnetic properties such as the half-metallicity, the conductivity and the magnetic moment distribution are investigated by performing first-principles calculations within the generalized gradient approximation for the exchange-correlation function based on density functional theory. Results show that ferromagnetic FeO has 100% spin-polarization at the Fermi level. Its supercell magnetic moments are 32.00 μB, which arise mainly from 3d-orbits of Fe-ions. The electronic structures of Fe-ions are Fe2+t2g3↑eg2↑t*2g1↓. 展开更多
关键词 half-metalLICITY Electric and MAGNETIC Properties SUPERCELL MAGNETIC MOMENTS
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Study of Half-Metallicity of Half-Heusler GeLiCa by Using mBJ Potential Method
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作者 T. Malsawmtluanga R. K. Thapa 《材料科学与工程(中英文A版)》 2017年第6期297-302,共6页
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Ruddlesden-Popper层状钙钛矿Bi_(8)Ba_(4)Mn_(8)O_(28)的电子结构与磁性的第一性原理
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作者 张铭 张持 +4 位作者 王朝 彭铠 李赛楠 马林昊 王如志 《北京工业大学学报》 CAS CSCD 北大核心 2024年第6期665-673,共9页
采用基于密度泛函理论的投影平面波方法,对Ruddlesden-Popper(RP)层状钙钛矿结构Bi_(8)Ba_(4)Mn_(8)O_(28)的电子结构和磁学性质进行了自旋极化计算。由于A位Ba的替位掺杂,造成MnO6八面体发生显著旋转、倾斜等畸变,会对电子结构与磁性... 采用基于密度泛函理论的投影平面波方法,对Ruddlesden-Popper(RP)层状钙钛矿结构Bi_(8)Ba_(4)Mn_(8)O_(28)的电子结构和磁学性质进行了自旋极化计算。由于A位Ba的替位掺杂,造成MnO6八面体发生显著旋转、倾斜等畸变,会对电子结构与磁性产生较大影响,对此进行了充分的讨论。考虑在位库伦作用修正的广义梯度近似(GGA+U)的计算表明,Bi_(8)Ba_(4)Mn_(8)O_(28)基态为铁磁半金属,其半金属能隙3.07 eV,晶胞总磁矩为31μB。Bi_(8)Ba_(4)Mn_(8)O_(28)的晶胞磁矩主要来自Mn原子磁矩的贡献,而Bi、Ba与O原子磁矩相对较小;而半金属性则主要源于Mn 3d自旋向上与自旋向下电子间存在较大的交换劈裂所致。使晶胞承受均匀变形,当其晶格常数在-10%~14%较大范围变化时,半金属性均可得到保持,且其晶胞总磁矩可始终稳定于31μB。 展开更多
关键词 第一性原理 层状钙钛矿 半金属 磁性 电子结构 晶格形变
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A位有序四重钙钛矿氧化物:结构、物性和展望
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作者 王潇 刘哲宏 +3 位作者 卢达标 皮茂材 潘昭 龙有文 《高压物理学报》 CAS CSCD 北大核心 2024年第1期1-24,共24页
A位有序四重钙钛矿氧化物AA′3B4O12具有丰富的物理性质和优异的材料性能,是当今凝聚态物理和材料科学的重要研究对象。相较于简单的ABO3型钙钛矿,在A位有序四重钙钛矿氧化物中,3/4的A位离子被过渡金属离子A′所取代,形成了1∶3的A/A′... A位有序四重钙钛矿氧化物AA′3B4O12具有丰富的物理性质和优异的材料性能,是当今凝聚态物理和材料科学的重要研究对象。相较于简单的ABO3型钙钛矿,在A位有序四重钙钛矿氧化物中,3/4的A位离子被过渡金属离子A′所取代,形成了1∶3的A/A′有序结构。因此,A位有序四重钙钛矿氧化物中的磁-电相互作用不再局限于B位子晶格内部,新颖的A′-A′、A′-B等磁-电相互作用也随之产生,从而展现出许多新现象和新物理机制,并为未来的实际应用提供了材料基础。围绕几种具有代表性的A位有序四重钙钛矿氧化物,回顾其研究脉络,对其晶体结构、物理性质和内在机理进行简单介绍,并对这类材料体系的研究方向和应用前景做出一些展望。 展开更多
关键词 高压制备 钙钛矿氧化物 介电性 电荷有序 多铁性 半金属
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Enhancement of the thermoelectric performance of half-metallic full-Heusler Mn_(2)VAl alloys via antisite defect engineering and Si partial substitution
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作者 Hezhang Li Kei Hayashi +4 位作者 Zhicheng Huang Hiroto Takeuchi Gakuto Kanno Jing-Feng Li Yuzuru Miyazaki 《Journal of Materiomics》 SCIE CSCD 2024年第2期511-519,共9页
A half-metallic full-Heusler Mn_(2)VAl alloy is a potential p-type thermoelectric material that can directly generate electricity from waste heat via the Seebeck effect.For practical use,the Seebeck coefficient S of M... A half-metallic full-Heusler Mn_(2)VAl alloy is a potential p-type thermoelectric material that can directly generate electricity from waste heat via the Seebeck effect.For practical use,the Seebeck coefficient S of Mn_(2)VAl should be increased while maintaining a high electrical conductivity s from its half-metallic character.Herein,we achieved this objective through antisite defect engineering.Theoretically,it was predicted that the S was maximized by regulating partial density of states of majority-spin sp-electrons through the control of the fraction of antisite defect,f_(AD),between V and Al atoms in Mn_(2)VAl.Experi-mentally,a significant increase in S and a slight decrease in s were observed for an Mn_(2)VAl sample with an optimal fAD=33%,enhancing the thermoelectric power factor PF by 2.7 times from an Mn_(2)VAl sample with fAD=14%.Furthermore,we combined the antisite defect engineering with a partial substitution method.An Mn_(2)V(Al_(0.96)Si_(0.04))sample with fAD=33%exhibited the highest PF=4.5×10^(-4)W·m^(-1)·K^(-2)at 767 K among the samples.The maximum dimensionless figure-of-merit zT of the Mn_(2)V(Al_(0.96)Si_(0.04))sample with f_(AD)=33%was measured to be 3.4×10^(-2)at 767 K,which is the highest among the p-type half-metallic full-Heusler alloys. 展开更多
关键词 half metal Full-Heusler alloy Thermoelectric properties Antisite defect Partial substitution
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