Amplification by stimulated emission of nitrogen vacancy centres in a diamond-loaded fibre cavity

TL;DR

This paper demonstrates stimulated emission and amplification in a diamond-loaded fibre cavity using nitrogen-vacancy centres, advancing the development of NV-based lasers for enhanced magnetometry.

Contribution

It experimentally explores a tunable fibre-cavity system with NV- centres, showing amplification and stimulated emission, which is a step toward NV-based diamond lasers.

Findings

Amplification of a seed laser at 721 nm observed with NV- centres.

Stimulated emission confirmed by increased emission intensity.

Qualitative model matches experimental dynamics well.

Abstract

Laser-threshold magetometry using the negatively charged nitrogen-vacancy (NV-) centre in diamond as a gain medium has been proposed as a technique to dramatically enhance the sensitivity of room-temperature magnetometry. We experimentally explore a diamond-loaded open tunable fibre-cavity system as a potential contender for the realization of lasing with NV- centres. We observe amplification of the transmission of a cavity-resonant seed laser at 721 nm when the cavity is pumped at 532 nm, and attribute this to stimulated emission. Changes in the intensity of spontaneously emitted photons accompany the amplification, and a qualitative model including stimulated emission and ionisation dynamics of the NV- centre captures the dynamics in the experiment very well. These results highlight important considerations in the realization of an NV- laser in diamond.