Driven coherent oscillations of a single electron spin in a quantum dot

TL;DR

This paper demonstrates the experimental control of a single electron spin in a quantum dot through driven coherent oscillations, showing potential for quantum computing applications.

Contribution

It reports the first realization of coherent single electron spin rotations in a double quantum dot using on-chip oscillating magnetic fields.

Findings

Observation of electron spin resonance via spin-dependent transport.

Demonstration of Rabi oscillations with about eight cycles.

Confirmation of single-electron spins as viable quantum bits.

Abstract

The ability to control the quantum state of a single electron spin in a quantum dot is at the heart of recent developments towards a scalable spin-based quantum computer. In combination with the recently demonstrated exchange gate between two neighbouring spins, driven coherent single spin rotations would permit universal quantum operations. Here, we report the experimental realization of single electron spin rotations in a double quantum dot. First, we apply a continuous-wave oscillating magnetic field, generated on-chip, and observe electron spin resonance in spin-dependent transport measurements through the two dots. Next, we coherently control the quantum state of the electron spin by applying short bursts of the oscillating magnetic field and observe about eight oscillations of the spin state (so-called Rabi oscillations) during a microsecond burst. These results demonstrate the feasibility of operating single-electron spins in a quantum dot as quantum bits.