Experimental fault-tolerant universal quantum gates with solid-state spins under ambient conditions

TL;DR

This paper demonstrates high-fidelity universal quantum gates in solid-state spins at room temperature, advancing fault-tolerant quantum computing under ambient conditions.

Contribution

It reports the first implementation of universal quantum gates with fidelities suitable for fault-tolerance in solid-state spins at room temperature.

Findings

Single-qubit gate fidelity of 0.999952

Two-qubit gate fidelity of 0.992

High control fidelities achieved in natural diamond at ambient conditions

Abstract

Quantum computation provides great speedup over its classical counterpart for certain problems. One of the key challenges for quantum computation is to realize precise control of the quantum system in the presence of noise. Control of the spin-qubits in solids with the accuracy required by fault-tolerant quantum computation under ambient conditions remains elusive. Here, we quantitatively characterize the source of noise during quantum gate operation and demonstrate strategies to suppress the effect of these. A universal set of logic gates in a nitrogen-vacancy centre in diamond are reported with an average single-qubit gate fidelity of 0.999952 and two-qubit gate fidelity of 0.992. These high control fidelities have been achieved at room temperature in naturally abundant 13C diamond via composite pulses and an optimized control method.