The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from ...The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from their highly tunable properties.In this article,the influence of Fe intercalation in NbSe_(2)was elaborately investigated using a combination of techniques.Magnetic studies have shown that the insertion of Fe atoms induces an antiferromagnetic state in which the easy axis aligns out of the plane.The sign reversal of the magnetoresistance across the Neel temperature can be satisfactorily explained by the moderate interaction between electrons and local spins.The Hall and Seebeck measurements reveal a multi-band nature,and the contribution of various phonon scattering processes is discussed based on the thermal conductivity and specific heat data.展开更多
An explicit function expression for the bias voltage or/and temperature dependences of tunnel magnetoresistance ratio and resistances were obtained with a unique set of intrinsic parameters. Two of these intrinsic par...An explicit function expression for the bias voltage or/and temperature dependences of tunnel magnetoresistance ratio and resistances were obtained with a unique set of intrinsic parameters. Two of these intrinsic parameters are the Curie temperature TC and the density of state (DOS) for itinerant majority and minority electrons ξ(ρM/ρm), which are the eigen parameters of ferromagnetic electrodes. Others are the spin-dependent matrix-element ratio (i.e., |Td|2/|TJ|2 ) and the anisotropic-wavelength-cutoff energy ECγ of spin-wave spectrum in magnetic tunnel junction (MTJ), which are the structure parameters of an MTJ. These intrinsic parameters can be predetermined using the experimental measurement or, in principle, using the first-principle calculation method for an MTJ with the three key layers of FM/I/FM. Furthermore, a series of experimental data for an MTJ, for example, a spin-valve-type MTJ of Ta (5 nm)/Ni79Fe21(25 nm)/lr22Mn78(12 nm)/Co75Fe25(4 nm)/AI(0.8 nm)-oxide/Co75Fe25(4 nm)/Ni79Fe21(20 nm)/Ta (5 nm) in this work, can be self-consistently evaluated and explained using such concise explicit function formulations.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.12274440)the National Key R&D Program of China(Grant No.2022YFA1403903)+1 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB33010100)the Fund of the Synergetic Extreme Condition User Facility(SECUF)。
文摘The interaction between charge and spin degrees of freedom has always been the central issue of condensed matter physics,and transition metal dichalcogenides(TMDs)provide an ideal platform to study it benefiting from their highly tunable properties.In this article,the influence of Fe intercalation in NbSe_(2)was elaborately investigated using a combination of techniques.Magnetic studies have shown that the insertion of Fe atoms induces an antiferromagnetic state in which the easy axis aligns out of the plane.The sign reversal of the magnetoresistance across the Neel temperature can be satisfactorily explained by the moderate interaction between electrons and local spins.The Hall and Seebeck measurements reveal a multi-band nature,and the contribution of various phonon scattering processes is discussed based on the thermal conductivity and specific heat data.
基金This work was supported by 2000 Hundred Talents Program project of Chinese Academy of Sciences and 973 project with Grant No. 2001CB610601 of PRC Ministry of Science and Technology. X.F.Han also gratefully acknowledges the partial support of K.C.Wong Edu
文摘An explicit function expression for the bias voltage or/and temperature dependences of tunnel magnetoresistance ratio and resistances were obtained with a unique set of intrinsic parameters. Two of these intrinsic parameters are the Curie temperature TC and the density of state (DOS) for itinerant majority and minority electrons ξ(ρM/ρm), which are the eigen parameters of ferromagnetic electrodes. Others are the spin-dependent matrix-element ratio (i.e., |Td|2/|TJ|2 ) and the anisotropic-wavelength-cutoff energy ECγ of spin-wave spectrum in magnetic tunnel junction (MTJ), which are the structure parameters of an MTJ. These intrinsic parameters can be predetermined using the experimental measurement or, in principle, using the first-principle calculation method for an MTJ with the three key layers of FM/I/FM. Furthermore, a series of experimental data for an MTJ, for example, a spin-valve-type MTJ of Ta (5 nm)/Ni79Fe21(25 nm)/lr22Mn78(12 nm)/Co75Fe25(4 nm)/AI(0.8 nm)-oxide/Co75Fe25(4 nm)/Ni79Fe21(20 nm)/Ta (5 nm) in this work, can be self-consistently evaluated and explained using such concise explicit function formulations.
