Single-photon, cavity-mediated gates: detuning, losses, and non-adiabatic effects

TL;DR

This paper analyzes extensions of cavity-mediated quantum gates involving single photons, focusing on detuning, losses, and nonadiabatic effects, to improve practical implementation and reduce pulse duration requirements.

Contribution

It extends previous gate proposals to more realistic configurations and identifies conditions to minimize nonadiabatic corrections, aiding experimental realization.

Findings

Leading nonadiabatic correction can be eliminated with proper detuning.

High cavity quality reduces the need for long photon pulses.

Analysis estimates effects of imperfections on gate performance.

Abstract

We study several extensions of the single-photon, cavity-mediated quantum logical gates recently proposed by Koshino, Ishizaka and Nakamura: to a double-sided cavity configuration, to the case where the two atomic ground states are nondegenerate, and to include nonadiabatic corrections. Our analysis can be used to estimate the effects of various imperfections, and to prepare the way for a proof-of-principle demonstration with present technology. An interesting result is that the leading correction to the adiabatic approximation can be made to vanish for a suitable choice of detunings, provided the cavity is "good enough" (high enough ratio of coupling to loss). This could significantly relax the need for long single-photon pulses.