Entangling homogeneously broadened matter qubits in the weak-coupling cavity-QED regime

TL;DR

This paper demonstrates that high-fidelity entanglement of homogeneously broadened matter qubits can be achieved in the weak-coupling cavity-QED regime, reducing technological demands for distributed quantum computing.

Contribution

It introduces a method for entangling matter qubits in the weak-coupling regime, bypassing the need for strong coupling typically required in cavity QED.

Findings

High-fidelity entanglement is possible in the weak-coupling regime.

The approach tolerates damping mechanisms like dephasing and cavity leakage.

Enables quantum information processing with less demanding experimental setups.

Abstract

In distributed quantum information processing, flying photons entangle matter qubits confined in cavities. However, when a matter qubit is homogeneously broadened, the strong-coupling regime of cavity QED is typically required, which is hard to realize in actual experimental setups. Here, we show that a high-fidelity entanglement operation is possible even in the weak-coupling regime in which dampings (dephasing, spontaneous emission, and cavity leakage) overwhelm the coherent coupling between a qubit and the cavity. Our proposal enables distributed quantum information processing to be performed using much less demanding technology than previously.