Ferromagnetic materials exhibiting low magnetic damping (α) and moderately high-saturation magnetization are required from the viewpoints of generation, transmission, and detection of spin waves. Since spin-to-charge conversion efficiency is another important parameter, high spin mixing conductance $$({g_{r}^{\uparrow \downarrow}})$$( g r ↑ ↓ ) is the key for efficient spin-to-charge conversion. Full Heusler alloys, e.g., Co₂Fe_0.4Mn_0.6Si (CFMS), which are predicted to be 100% spin-polarized, exhibit low α. However, $$g_r^{ \uparrow \downarrow }$$g r ↑ ↓ at the interface between CFMS and a paramagnet is not fully understood. Here, we report investigations of spin pumping and the inverse spin Hall effect in CFMS/Pt bilayers. Damping analysis indicates the presence of significant spin pumping at the interface of CFMS and Pt, which is also confirmed by the detection of an inverse spin Hall voltage. We show that in CFMS/Pt, $$g_r^{ \uparrow \downarrow }$$g r ↑ ↓ (1.70 × 10²⁰ m⁻²) and the interface transparency (83%) are higher than the values reported for other ferromagnetic/heavy metal systems. We observed a spin Hall angle of ~0.026 for the CFMS/Pt bilayer system.

Manganites are an interesting class of materials because they exhibit high spin polarization and low damping. We observed both spin pumping and anti-damping in La _0.67 Sr _0.33 MnO ₃ /Pt system which makes it promising for future spintronic applications.

This article reports the dependence of exchange bias (EB) effect on interparticle interactions in nanocrystalline Co/CoO core/shell structures, synthesized using the conventional sol-gel technique. Analysis via powder X-Ray diffraction (PXRD) studies and transmission electron microscope (TEM) images confirm the presence of crystalline phases of core/shell Co/CoO with average particle size ≈ 18 nm. Volume fraction ($\phi$) is varied (from 20% to 1%) by the introduction of a stoichiometric amount of non-magnetic amorphous silica matrix (SiO${}_2$) which leads to a change in interparticle interaction (separation). The influence of exchange and dipolar interactions on the EB effect, caused by the variation in interparticle interaction (separation) is studied for a series of Co/CoO core/shell nanoparticle systems. Studies of thermal variation of magnetization ($M-T$) and magnetic hysteresis loops ($M-H$) for the series point towards strong dependence of magnetic properties on dipolar interaction in concentrated assemblies whereas individual nanoparticle response is dominant in isolated nanoparticle systems. The analysis of the EB effect reveals a monotonic increase of coercivity ($H_C$) and EB field ($H_E$) with increasing volume fraction. When the nanoparticles are close enough and the interparticle interaction is significant, collective behavior leads to an increase in the effective antiferromagnetic (AFM) CoO shell thickness which results in high $H_C$ and $H_E$. Moreover, in concentrated assemblies, the dipolar field superposes to the local exchange field and enhances the EB effect contributing as an additional source of unidirectional anisotropy.

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 .