Fast spin-orbit qubit in an indium antimonide nanowire

TL;DR

This paper demonstrates fast, electrically controlled spin-orbit qubits in indium antimonide nanowires with high Rabi frequencies and measurable coherence times, advancing quantum computing capabilities.

Contribution

It reports the first observation of Rabi oscillations exceeding 100 MHz in InSb nanowire spin-orbit qubits and details their coherence properties.

Findings

Rabi frequencies >100 MHz achieved

Coherence time T_2* = 8 ns, extended to 35 ns with Hahn echo

Individual qubits addressable via g-factor differences

Abstract

Due to the strong spin-orbit interaction in indium antimonide, orbital motion and spin are no longer separated. This enables fast manipulation of qubit states by means of microwave electric fields. We report Rabi oscillation frequencies exceeding 100 MHz for spin-orbit qubits in InSb nanowires. Individual qubits can be selectively addressed due to intrinsic dierences in their g-factors. Based on Ramsey fringe measurements, we extract a coherence time T_2* = 8 +/- 1 ns at a driving frequency of 18.65 GHz. Applying a Hahn echo sequence extends this coherence time to 35 ns.