In:
Acta Physica Sinica, Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences, Vol. 0, No. 0 ( 2023), p. 0-
Abstract:
Two-dimensional semiconductor materials with intrinsic magnetism have great application prospects in realizing spintronic devices with low power consumption, small size and high efficiency. Some two-dimensional materials with special lattice structures, such as kagome lattice crystals, are favored by researchers because of their novel properties in magnetism and electronic properties. Recently, a new two-dimensional magnetic semiconductor material Nb〈sub〉3〈/sub〉Cl〈sub〉8〈/sub〉 monolayer with kagome lattice structure was successfully prepared, which provides a new platform for exploring two-dimensional magnetic semiconductor devices with kagome structure. In this work, we study the electronic structure and magnetic anisotropy of Nb〈sub〉3〈/sub〉Cl〈sub〉8〈/sub〉 monolayer. We also further construct its 〈em〉p-n〈/em〉 junction diode and study its spin transport properties by using density functional theory combined with non-equilibrium Green's function method. The results show that the phonon spectrum of the Nb〈sub〉3〈/sub〉Cl〈sub〉8〈/sub〉 monolayer has no negative frequency, confirming its dynamic stability. The band gap of the spin-down state (1.157 eV) is significantly larger than that of the spin-up state (0.639 eV). The magnetic moment of the Nb〈sub〉3〈/sub〉Cl〈sub〉8〈/sub〉 monolayer is 0.997 μ〈sub〉B〈/sub〉, and its easy magnetization axis is in the plane and along the 〈em〉x〈/em〉 axis direction based on its energy of magnetic anisotropy. Nb atoms make the main contribution to the magnetic anisotropy. When the strain is applied, the band gap of the spin-down states will decrease, while the band gap of the spin-up state is monotonously decreased from the negative (compress) to positive (tensile) strain. As the strain variable goes from -6% to 6%, the contribution of Nb atoms to the total magnetic moment gradually increases. Moreover, strain causes the easy magnetization axis of the Nb〈sub〉3〈/sub〉Cl〈sub〉8〈/sub〉 monolayer to flip vertically from in-plane to out-plane. The designed 〈em〉p-n〈/em〉 junction diode nanodevice based on Nb〈sub〉3〈/sub〉Cl〈sub〉8〈/sub〉 monolayer exhibits an obvious rectification effect. In addition, the current in the spin-up state is larger than that in the spin-down state, exhibiting a spin-polarized transport behavior. Moreover, a negative differential resistance (NDR) phenomenon is also observed, which could be used in the NDR devices. These results demonstrate that the Nb〈sub〉3〈/sub〉Cl〈sub〉8〈/sub〉 monolayer material has great potential application in the next generation of high-performance spintronic devices, and further experimental verification and exploration of this material and related two-dimensional materials are needed.
Type of Medium:
Online Resource
ISSN:
1000-3290
,
1000-3290
DOI:
10.7498/aps.73.20231163
Language:
Unknown
Publisher:
Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
Publication Date:
2023
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