半導体ナノワイヤ電界効果トランジスタにおけるスピン軌道相互作用の高効率電界制御

抄録

Spin-orbit interaction, which couples electron spin to its momentum, is a relativistic effect that appears in solid-states physics. Specifically, Rashba spin-orbit interaction, which is proportional to external electric field, plays a key role in realizing novel devices such as a spin FET and topological computers. Here, we report high gate controllability of the spin-orbit interaction in III-V semiconductor nanowire transistors with various geometries. We demonstrate a gate-all-around InAs nanowire transistor and a nearby back-gate InSb nanowire transistor, both of which enable us to apply strong electric field to an electron channel. Consequently, the gate tunability of Rashba spin-orbit interaction is more than ten times higher than those reported for III-V semiconductor FETs, including nanowire FETs with a standard back-gate geometry and Schottky FETs fabricated from two-dimensional quantum wells, all of which were studied as candidates of a spin FET. Our results pave a way toward realizing a nanoscale spin FET in the future.