Continuous-wave nitrogen-vacancy diamond laser system assisted by a red diode laser

TL;DR

This paper reports the first continuous-wave laser system using nitrogen-vacancy centers in diamond, combining a diamond medium with a diode laser to achieve laser threshold and linewidth narrowing, advancing magnetometry techniques.

Contribution

Demonstration of the first continuous-wave NV-diamond laser system with a dual-medium cavity and intra-cavity diode laser assistance.

Findings

Achieved the first CW laser threshold with NV centers.

Observed linewidth narrowing with increased pump power.

Developed a dual-medium laser cavity for NV-diamond lasing.

Abstract

Diamond has long been identified as a potential host material for laser applications. This potential arises due to its exceptional thermal properties, ultra-wide bandgap, and color centers which promise gain across the visible spectrum. More recently, coherent laser methods offer new approaches to magnetometry. However, diamond fabrication is difficult in comparison to other crystalline matrices, and many optical loss channels are not yet understood. Here, we demonstrate the first continuous-wave nitrogen-vacancy (NV) color center laser system. To achieve this, we constructed a laser cavity with both, an NV-diamond medium and an intra-cavity anti-reflection coated diode laser. This dual-medium approach compensates intrinsic losses of the cavity by providing a fixed additional gain below threshold of the diode laser. We observe the first clear continuous-wave laser threshold in the output of the laser system as well as linewidth narrowing with increasing green pump power on the NV centers. Our results are a major development towards coherent approaches to magnetometry.