Spin relaxation in (110)GaAs superlattices with tunnel-coupled quantum wells for both lateral and vertical spin transport

Long-range spin transport at room temperature is one of the indispensable technologies for realizing spintronics devices. In this study, we have investigated electron spin relaxation time of (110)-oriented GaAs superlattice having tunnel-coupled quantum wells for both lateral and vertical spin transport. It was revealed that the spin relaxation time at room temperature was 0.7 ns, about 7 times longer than that of bulk GaAs which has been used for conventional spin transport layer of spin-controlled lasers. This finding provides a novel method of controlling the spin relaxation time at room temperature and indicates that the superlattice structures are promising for spin transport layers in semiconductor-based spintronics devices.