Engineering Atomic Quantum Reservoirs for Photons

TL;DR

This paper proposes a robust method to generate entangled photon states in microwave cavities using atomic beams acting as quantum reservoirs, without needing atomic detection or velocity control.

Contribution

It introduces protocols leveraging stochastic atomic interactions to produce and control entangled cavity states, advancing quantum reservoir engineering techniques.

Findings

Successfully creates entangled cavity modes via atomic beams.

The entanglement degree is tunable by the transverse field parameters.

The scheme is resilient to atomic beam fluctuations.

Abstract

We present protocols for creating entangled states of two modes of the electromagnetic field, by using a beam of atoms crossing microwave resonators. The atoms are driven by a transverse, classical field and pump correlated photons into (i) two modes of a cavity and (ii) the modes of two distant cavities. The protocols are based on a stochastic dynamics, characterized by random arrival times of the atoms and by random interaction times between atoms and cavity modes. The resulting effective model yields a master equation, whose steady state is an entangled state of the cavity modes. In this respect, the atoms act like a quantum reservoir, pulling the cavity modes into an entangled, Einstein-Podolski-Rosen (EPR) state, whose degree of entanglement is controlled by the intensity and the frequency of the transverse field. This scheme is robust against stochastic fluctuations in the atomic beam, and it does not require atomic detection nor velocity selection.