All-electric all-semiconductor spin field effect transistors

TL;DR

This paper introduces an all-electric, all-semiconductor spin field effect transistor that overcomes previous challenges by using quantum point contacts for spin injection and detection, enabling integrated spintronic devices.

Contribution

It presents a novel spin transistor design employing quantum point contacts and engineered spin-orbit coupling for complete electrical control of electron spins.

Findings

Achieved full electrical control of spin injection, manipulation, and detection.

Compatible with large-scale integration for future spintronic applications.

Overcame fundamental challenges like resistance mismatch and spin relaxation.

Abstract

The spin field effect transistor envisioned by Datta and Das opens a gateway to spin information processing. Although the coherent manipulation of electron spins in semiconductors is now possible, the realization of a functional spin field effect transistor for information processing has yet to be achieved, owing to several fundamental challenges such as the low spin-injection efficiency due to resistance mismatch, spin relaxation, and the spread of spin precession angles. Alternative spin transistor designs have therefore been proposed, but these differ from the field effect transistor concept and require the use of optical or magnetic elements, which pose difficulties for the incorporation into integrated circuits. Here, we present an all-electric and all-semiconductor spin field effect transistor, in which these obstacles are overcome by employing two quantum point contacts as spin injectors and detectors. Distinct engineering architectures of spin-orbit coupling are exploited for the quantum point contacts and the central semiconductor channel to achieve complete control of the electron spins -- spin injection, manipulation, and detection -- in a purely electrical manner. Such a device is compatible with large-scale integration and hold promise for future spintronic devices for information processing.