Fock-state stabilization and emission in superconducting circuits using dc-biased Josephson junctions

TL;DR

This paper proposes a reservoir-engineering method using dc-biased Josephson junctions to stabilize and generate Fock states in superconducting microwave cavities without microwave control drives.

Contribution

It introduces a novel approach that stabilizes and produces Fock states using only dc bias and cavity coupling, eliminating the need for microwave pulses.

Findings

Fock states can be stabilized with high fidelity.

The system can generate on-demand propagating Fock states.

No microwave-frequency control drives are required.

Abstract

We present and analyze a reservoir-engineering approach to stabilizing Fock states in a superconducting microwave cavity which does not require any microwave-frequency control drives. Instead, our system makes use of a Josephson junction biased by a dc voltage which is coupled both to a principle storage cavity and a second auxiliary cavity. Our analysis shows that Fock states can be stabilized with an extremely high fidelity. We also show how the same system can be used to prepare on-demand propagating Fock states, again without the use of microwave pulses.