Continuous wave single photon transistor based on a superconducting circuit

TL;DR

This paper introduces a continuous wave microwave single photon transistor using a superconducting circuit, enabling efficient, passive photon detection with robustness to noise and feasible implementation with current technology.

Contribution

It presents a passive, continuous wave single photon transistor design based on a superconducting circuit, advancing microwave photon detection technology.

Findings

Achieves full absorption of a control photon into hybridized states.

Demonstrates photon flux output with low dark counts and robustness.

Compatible with existing superconducting circuit technology.

Abstract

We propose a microwave frequency single photon transistor which can operate under continuous wave probing, and represents an efficient single microwave photon detector. It can be realized using an impedance matched system of a three level artificial ladder-type atom coupled to two microwave cavities connected to input/output waveguides. Using a classical drive on the upper transition, we find parameter space where a single photon control pulse incident on one of cavities can be fully absorbed into hybridized excited states. This subsequently leads to series of quantum jumps in the upper manifold and the appearance of a photon flux leaving the second cavity through a separate input/output port. The proposal does not require time variation of the probe signals, thus corresponding to a passive version of single photon transistor. The resulting device is robust to qubit dephasing processes, possesses low dark count rate for large anharmonicity, and can be readily implemented using current technology.