Circuit Quantum Electrodynamics with a Superconducting Quantum Point Contact

TL;DR

This paper explores coupling a superconducting quantum point contact with a resonator in circuit QED, demonstrating the feasibility of strong and ultrastrong coupling regimes with current technology.

Contribution

It introduces configurations for coupling a quantum point contact to a resonator and shows that strong and ultrastrong coupling are achievable with realistic parameters.

Findings

Strong and ultrastrong coupling regimes are feasible.

Coherent exchange between quantum point contact and cavity field demonstrated.

Configurations compatible with current technology are proposed.

Abstract

We consider a superconducting quantum point contact in a circuit quantum electrodynamics setup. We study three different configurations, attainable with current technology, where a quantum point contact is coupled galvanically to a coplanar waveguide resonator. Furthermore, we demonstrate that the strong and ultrastrong coupling regimes can be achieved with realistic parameters, allowing the coherent exchange between a superconducting quantum point contact and a quantized intracavity field.