Driving spin and charge in quantum wells by surface acoustic waves

Abstract

Recent experiments have shown the potential of surface acoustic waves as a mean for transporting charge and spin in quantum wells. In particular, they have proven highly effective for the coherent transport of spin-polarized wave packets, suggesting their potential in spintronics applications. Motivated by these experimental observations, we have theoretically studied the spin and charge dynamics in a quantum well under surface acoustic waves. We show that the dynamics acquires a simple and transparent form in a reference frame co-moving with the surface acoustic wave. Our results, e.g., the calculated spin relaxation and precession lengths, are in excellent agreement with recent experimental observations.