Spin and charge conversion in topological surface states and oxide interface states

Spin and charge conversion has attracted a lot of interest in the field of spintronics. Two major mechanisms have been utilized to do the spin and charge conversion are spin Hall effect and Edelstein effect. For Edelstein effect, it refers to spin current conversion from charge current flowing in inversion asymmetric two-dimensional electron gases (2DEGs) with large Rashba spin orbit coupling.

In this talk, I will present the spin and charge conversion using the topological surface states and Rashba-split 2DEG. In the first one [1], I will describe our experimental results that demonstrate the spin injection and the inverse Edelstein effect in the spin-momentum locked surface states of a topological Kondo insulator, SmB6. I will also discuss the spin pumping efficiency between the topological surface states and a ferrimagnetic insulator (YIG) due to interfacial s-d exchange interaction. In the second part of my talk , I will discuss the gate-tunable the inverse Edelstein effect up to room temperature in the Rashba-split 2DEG between SrTiO3 and LaAlO3 [2].

References:
[1] Song, et al, “Spin Injection and Inverse Edelstein Effect in the Surface States of Topological Kondo Insulator SmB6”, Nature Communications, 7:13485 (2016).
[2] Song, et al, “Observation of Inverse Edelstein Effect in Rashba-Split 2DEG between SrTiO3 and LaAlO3 at Room Temperature”, Science Advances, 3, e1602312 (2017).