Electrical control over single hole spins in nanowire quantum dots

TL;DR

This paper demonstrates electrical control over single hole spins in nanowire quantum dots, highlighting their potential for quantum information processing due to unique properties like strong spin-orbit interaction and weak hyperfine coupling.

Contribution

It reports the fabrication of gate-tuneable hole quantum dots in InSb nanowires and demonstrates electrical control of single hole spins, enabling direct comparison with electron spins.

Findings

Demonstrated Pauli spin blockade in hole quantum dots

Achieved electrical control of single hole spins

Compared hyperfine interactions and g-factors between hole and electron regimes

Abstract

Single electron spins in semiconductor quantum dots (QDs) are a versatile platform for quantum information processing, however controlling decoherence remains a considerable challenge. Recently, hole spins have emerged as a promising alternative. Holes in III-V semiconductors have unique properties, such as strong spin-orbit interaction and weak coupling to nuclear spins, and therefore have potential for enhanced spin control and longer coherence times. Weaker hyperfine interaction has already been reported in self-assembled quantum dots using quantum optics techniques. However, challenging fabrication has so far kept the promise of hole-spin-based electronic devices out of reach in conventional III-V heterostructures. Here, we report gate-tuneable hole quantum dots formed in InSb nanowires. Using these devices we demonstrate Pauli spin blockade and electrical control of single hole spins. The devices are fully tuneable between hole and electron QDs, enabling direct comparison between the hyperfine interaction strengths, g-factors and spin blockade anisotropies in the two regimes.