Narrow-band single photon emission at room temperature based on a single Nitrogen-vacancy center coupled to an all-fiber-cavity

TL;DR

This paper demonstrates a fiber-coupled single photon source using a nitrogen-vacancy center in diamond within an all-fiber cavity, achieving high spectral photon density and tunability for quantum network applications.

Contribution

The work introduces a novel all-fiber cavity device with a single NV center, enabling efficient, tunable, and fiber-integrated single photon emission at room temperature.

Findings

Spectral photon rate density increased by two orders of magnitude.

Device is fiber-coupled and tunable via mirror separation.

Promising for integration into photonic quantum networks.

Abstract

We report the realization of a device based on a single Nitrogen-vacancy (NV) center in diamond coupled to a fiber-cavity for use as single photon source (SPS). The device consists of two concave mirrors each directly fabricated on the facets of two optical fibers and a preselected nanodiamond containing a single NV center deposited onto one of these mirrors. Both, cavity in- and output are directly fiber-coupled and the emission wavelength is easily tunable by variation of the separation of the two mirrors with a piezo-electric crystal. By coupling to the cavity we achieve an increase of the spectral photon rate density by two orders of magnitude compared to free-space emission of the NV center. With this work we establish a simple all-fiber based SPS with promising prospects for the integration into photonic quantum networks.