2D 반데르발스 반강자성 MPS3 (M=Mn, Co, and Fe)를 기반으로 한 스핀 칼로리트로닉 소자에 관한 연구

Abstract

Spin-caloritronics is an emerging field that combines spintronics, thermoelectrics (TEs), and thermomagnetics, offering new possibilities for achieving high conversion efficiencies in low-dimensional systems. While TE devices (thermopiles) use the Seebeck effect to generate a voltage from a temperature gradient, spin-caloritronics materials use the thermally induced spin Seebeck effect (SSE), which generates the spin and pure spin current. Spin current, i.e., a flow of spin angular momentum or public magnetic moment via SSE, has recently attracted renewed attention as a potential alternative to charge current with improved energy efficiency. In metallic systems, the spin-polarized conduction electrons are the carriers of the spin current, whereas in insulating systems the spin-wave spin current (SWSC) is the carrier of the spin current. In particular, the spin-wave spin current (SWSC) has a much longer decay length and avoids the simultaneous flow of charge current and Joule heat loss, a strong advantage for spintronics. However, most magnetic insulators tend to be antiferromagnetic, and it is a critical question whether the spin waves in antiferromagnets can carry a spin current or not. Recently, S. Seki et al. have shown that the antiferromagnetic spin wave can be an efficient carrier of spin current, highlighting antiferromagnetic insulators as a promising source of unique spintronic functions. In this research work, we aim to investigate SSE using 2D vdW antiferromagnetic (AFM) MPS3 (M=Mn or Co) magnetic insulator as spin generator and heavy metal e.g. Pt, Ta, W, etc. (θSH in Pt, Ta, and W are in range of ∼0.012 to ∼0.15 and ∼0.33) or topological insulator e.g. Bi2Se3, etc. (θSH in Bi2Se3 varying from 0.01 to 3.5) as a spin detector. Keywords: Spintronics; Spin caloritronics; Spin Seebeck effect; Inverse spin Hall effect; 2D material; Antiferromagnetic; Spin-wave spin current; MPS3; Transition metal phosphorus trisulfide