Towards the Realization of a Quantum Computer Using Single Electron Spins in Si Quantum Dots

Abstract

Among many candidates for a quantum bit, electron spins in Si quantum dots are one of the most promising ones for its potential to scale up and its long coherence time. Its intrinsic coherence time of an electron spin in a Si quantum dot has been measured to be ～1 μs for natural Si and ～120 μs for isotopically purified Si. A universal single-qubit gate and a two-qubit logic gate have been experimentally demonstrated. The average gate fidelity of a single-qubit gate reached 99%, a threshold required for a quantum error correction. This recent progress paves the way for the realization for a quantum computer using single electron spins in Si quantum dots.