No abstract

Transition metal dichalcogenides (TMD) possess properties which makes them potential candidates for various spintronic applications. Heterostructures of TMD with magnetic thin film have been extensively considered for spin−orbital torque, enhancement of perpendicular magnetic anisotropy etc. However, the effect of TMD on magnetic anisotropy in heterostructures of in-plane magnetization has not been studied so far. Further the effect of the TMD on the domain structure and magnetization reversal of the ferromagnetic system is another important aspect to be understood. In this context we study the effect of MoS 2 , a well-studied TMD material, on magnetic properties of CoFeB in MoS 2 /CoFeB heterostructures. The reference CoFeB film possesses a weak in-plane anisotropy. However, when the CoFeB is deposited on MoS 2 the in-plane anisotropy is enhanced as observed from magneto optic Kerr effect (MOKE) microscopy as well as ferromagnetic resonance (FMR). Magnetic domain structure and magnetization reversal have also been significantly modified for the MoS 2 /CoFeB bilayer as compared to the reference CoFeB layer. Frequency and angle dependent FMR measurement show that the magnetic anisotropy of CoFeB increases with increase in thickness of MoS 2 in the MoS 2 /CoFeB heterostructures.

High spin to charge conversion efficiency is a requirement for spintronic devices, which are governed by spin pumping and the inverse spin Hall effect (ISHE). In the last decade, ISHE and spin pumping have been heavily investigated in ferromagnet/heavy metal (HM) heterostructures. Recently, antiferromagnetic (AFM) materials have been found to be a good replacement for HMs because AFMs exhibit terahertz spin dynamics, high spin-orbit coupling, and absence of the stray field. In this context, we have performed the ISHE in CoFeB/IrMn heterostructures. Spin pumping studies are carried out for Co 40 Fe 40 B 20 (12 nm)/Cu(3 nm)/ Ir 50 Mn 50 (t nm)/AlO x (3 nm) samples where t value varies from 0 to 10 nm. Damping in all the samples is higher than in the single layer CoFeB which indicates that spin pumping due to IrMn is the underneath mechanism. Further, the spin pumping in the samples is confirmed by angle dependent ISHE measurements. We have also disentangled other spin rectifications effects and found that the spin pumping is dominant in all the samples. From the ISHE analysis the real part of spin mixing conductance (g ↑↓ r ) is found to be 0.704 ± 0.003 × 10 18 m −2 .