Improving coherence times of quantum bits is a fundamental challenge in the field of quantum computing. With long-lived qubits it becomes, however, inefficient to wait until the qubits have relaxed to their ground state after completion of an experiment. Moreover, for error-correction schemes it is import to rapidly re-initialize ancilla parity-check qubits. We present a simple pulsed qubit reset protocol based on a two-pulse sequence. A first pulse transfers the excited state population to a higher excited qubit state and a second pulse into a lossy environment provided by a low-Q transmission line resonator, which is also used for qubit readout. We show that the remaining excited state population can be suppressed to 2.2±0.8% and utilize the pulsed reset protocol to carry out experiments at enhanced rates.
@article{arxiv.1802.08980,
title = {Pulsed reset protocol for fixed-frequency superconducting qubits},
author = {Daniel J. Egger and Max Werninghaus and Marc Ganzhorn and Gian Salis and Andreas Fuhrer and Peter Mueller and Stefan Filipp},
journal= {arXiv preprint arXiv:1802.08980},
year = {2019}
}