Quantum microwave-optical interface with nitrogen-vacancy centers in diamond

TL;DR

This paper proposes a scheme for a coherent quantum interface connecting microwave and optical photons via NV centers in diamond, enabling quantum state transfer for quantum information applications.

Contribution

It introduces a novel hybrid quantum interface using NV centers coupled to optical and microwave cavities, utilizing collective spin modes for efficient quantum state transfer.

Findings

Quantum states can be transferred between microwave and optical cavities.

The scheme employs double-swap and dark-state protocols.

Potential applications include microwave photon detection and quantum computing.

Abstract

We propose an efficient scheme for a coherent quantum interface between microwave and optical photons using nitrogen-vacancy (NV) centers in diamond. In this setup, an NV center ensemble is simultaneously coupled to an optical and a microwave cavity. We show that, by using the collective spin excitation modes as an intermediary, quantum states can be transferred between the microwave cavity and the optical cavity through either a double-swap scheme or a dark-state protocol. This hybrid quantum interface may provide interesting applications in single microwave photon detections or quantum information processing.