Entangling unstable optically active matter qubits

TL;DR

This paper presents a robust scheme for entangling unstable optically active matter qubits in distributed quantum systems, enabling high-fidelity operations despite state instability and system imperfections.

Contribution

The proposed protocol achieves high-fidelity entanglement without needing stable optical states or number-resolving detectors, applicable with or without cavities.

Findings

Effective entanglement protocol for unstable qubits

High fidelity achieved despite state instability

Operates with or without optical cavities

Abstract

In distributed quantum computation, small devices composed of a single or a few qubits are networker together to achieve a scalable machine. Typically there is an optically active matter qubit at each node, so that photons are exploited to achieve remote entanglement. However, in many systems the optically active states are unstable or poorly defined. We report a scheme to perform a high-fidelity entanglement operation even given severe instability. The protocol exploits the existence of optically excited states for phase acquisition without actually exciting those states; it functions with or without cavities and does not require number resolving detectors.