Nonvolatile modulation of spin transport in PMN-PT/LiFe5O8/Pt multiferroic heterostructures

Beside playing a keystone role in spin-field-effect transistor, electrical control of spin transport is also of fundamental and practical importance for many other spintronic devices due to the advantages of energy efficiency and versatility. In this work, we demonstrate a significant electrical modulation of spin transport in the PMN-PT/LiFe5O8/Pt heterostructures. The key spin transport parameters, including the spin Hall angle, spin diffusion length, and spin mixing conductance, were extracted through the thickness dependence of spin Hall magnetoresistance. It is found that the spin Hall angle decreases with the decrease in temperature, while the spin diffusion length keeps invariant with temperature, revealing the dominance of D'yakonov-Perel' type spin transport in LiFe5O8/Pt. Remarkably, by applying the electric field onto the piezoelectric PMN-PT substrate, the spin Hall angle of Pt can be modulated 28% and exhibits a nonvolatile hysteresis relationship with the applied electric field, which primarily originates from the modulation of Pt resistivity induced by the strain coupling through the ferroelastic domain switching of the ferroelectric PMN-PT substrate. Our results elucidate the spin transport characteristics in PMN-PT/LiFe5O8/Pt heterostructures and pave the way toward novel spintronic devices with electrically tunable spin current generation and transport processes. Published under an exclusive license by AIP Publishing.

Automated summary

Electrical modulation of spin transport was demonstrated in PMN-PT/LiFe5O8/Pt heterostructures, with significant changes in spin Hall angle and a nonvolatile hysteresis relationship observed. The dominance of D'yakonov-Perel' type spin transport in LiFe5O8/Pt was revealed, and the modulation of Pt's spin Hall angle was primarily attributed to strain coupling induced by ferroelastic domain switching of the ferroelectric PMN-PT substrate. This work paves the way for novel spintronic devices with electrically tunable spin current generation and transport processes.