Demonstrating a driven reset protocol for a superconducting qubit

Phys Rev Lett. 2013 Mar 22;110(12):120501. doi: 10.1103/PhysRevLett.110.120501. Epub 2013 Mar 20.

Abstract

Qubit reset is crucial at the start of and during quantum information algorithms. We present the experimental demonstration of a practical method to force qubits into their ground state, based on driving appropriate qubit and cavity transitions. Our protocol, called the double drive reset of population, is tested on a superconducting transmon qubit in a three-dimensional cavity. Using a new method for measuring population, we show that we can prepare the ground state with a fidelity of at least 99.5% in less than 3 μs; faster times and higher fidelity are predicted upon parameter optimization.