Magnetization dynamics and asymmetric Spin Pumping in Ni₈₀Fe₂₀/Cu/Cr_1.12Te₂ trilayer stack

Spin transport in magnetic stacks enables devices to operate at ultrafast speed while using low-power device operation. We report the temperature-dependent spin-current exchange between two ferromagnets in the trilayer structure of a ferromagnetic/normal/ferromagnetic (Cr_1.12Te₂/Cu/Ni₈₀Fe₂₀) stack. Spin transport dynamics across the Cr_1.12Te₂/Cu/Ni₈₀Fe₂₀ magnetic trilayer stack are determined by modulation of magnetization dynamical parameters including effective Gilbert damping coefficients (α_eff), effective magnetic fields (4πM_eff), interfacial spin mixing conductance (g^↑↓), and spin current density (J_s) by means of broadband cryogenic ferromagnetic resonance measurements. At a distinct precession of the individual magnetic layer, spin pumping is found to be prevalent with the expected linewidth increase. Subsequent observation of absence of interface damping shows the possible control of the spin-pumping effect by tuning the net flow of spin current in a multilayer structure. These experimental findings offer a valuable insight into the transmission and absorption of pure spin currents, and temperature-dependent, tuneable dynamical parameters in magnetic multilayers may be realized for next-generation spintronic devices.