Quantum Gates for Propagating Microwave Photons
Abstract
We report a generic scheme to implement transmission-type quantum gates for propagating microwave photons, based on a sequence of lumped-element components on transmission lines. By choosing three equidistant superconducting quantum interference devices (SQUIDs) as the components on a single transmission line, we experimentally implement a magnetic-flux-tunable phase shifter and demonstrate that it produces a broad range of phase shifts and full transmission within the experimental uncertainty. Together with previously demonstrated beam splitters, these phase shifters can be utilized to implement arbitrary single-qubit gates. Furthermore, we theoretically show that replacing the SQUIDs by superconducting qubits, the phase shifter can be made strongly nonlinear, thus introducing deterministic photon--photon interactions. These results critically complement the previous demonstrations of on-demand single-photon sources and detectors, and hence pave the way for an all-microwave quantum computer based on propagating photons.
Cite
@article{arxiv.1703.02241,
title = {Quantum Gates for Propagating Microwave Photons},
author = {Roope Kokkoniemi and Tuomas Ollikainen and Russell E. Lake and Sakari Saarenpää and Kuan Yen Tan and Janne I. Kokkala and Ceren B. Dağ and Joonas Govenius and Mikko Möttönen},
journal= {arXiv preprint arXiv:1703.02241},
year = {2017}
}