From blockade to transparency: controllable photon transmission through a circuit QED system

TL;DR

This paper investigates how the transmission of microwave photons in a circuit QED system can be controlled by the detecting field, revealing the conditions under which photon blockade occurs or is suppressed, with implications for quantum photonics.

Contribution

It demonstrates that photon transmission can be switched from blockade to transparency by controlling the detecting field in a superconducting circuit QED system, linking bistability and photon blockade.

Findings

Photon blockade cannot occur in the bistable regime.

Photon transmission can be controlled from blockade to transparency.

The proposal is feasible with current technology.

Abstract

A strong photon-photon nonlinear interaction is a necessary condition for photon blockade. Moreover, this nonlinearity can also result a bistable behavior in the cavity field. We analyze the relation between detecting field and photon blockade in a superconducting circuit QED system, and show that photon blockade cannot occur when the detecting field is in the bistable regime. This photon blockade is the microwave-photonics analog of the Coulomb blockade. We further demonstrate that the photon transmission through such system can be controlled (from photon blockade to transparency) by the detecting field. Numerical calculations show that our proposal is experimentally realizable with current technology.