Quantum information processing with a single photon by input-output process regarding low-Q cavities

TL;DR

This paper explores quantum information processing using single photons in low-Q cavities, presenting a general input-output framework and proposing schemes based on Faraday rotation for entangling atomic qubits.

Contribution

It introduces a general expression for the input-output process in low-Q cavities and proposes novel quantum information processing schemes utilizing Faraday rotation.

Findings

Derived a versatile input-output formula for low-Q cavities.

Proposed quantum schemes leveraging Faraday rotation with single photons.

Demonstrated potential for quantum entanglement in low-Q cavity systems.

Abstract

Both cavity QED and photons are promising candidates for quantum information processing. We consider a combination of both candidates with a single photon going through spatially separate cavities to entangle the atomic qubits, based on the input-output process of the cavities. We present a general expression for the input-output process regarding the low-Q cavity confining a single atom, which works in a wide range of parameters. Focusing on low-Q cavity case, we propose some schemes for quantum information processing with Faraday rotation using single photons, which is much different from the high-Q cavity and strong coupling cases.