Monolithic diamond Raman resonators for high resolution spectroscopy

Tunable and spectrally pure lasers at visible wavelengths are key tools for many applications in physics, metrology and quantum technology. Integrating these laser sources on wafer-scaled devices is necessary for scaling the technology, allowing for powerful quantum tools. Current implementations however, are composed by complex, bulky systems that are in no way suitable to be used in the mentioned applications. To tackle this, we propose monolithic diamond Raman resonators as scalable, tunable, single-frequency laser sources. In these resonators, lasing happens through stimulated Raman scattering, which under certain conditions allows for the production of narrow-linewidth Stokes laser fields. Diamond-bulk temperature changes are used here to tune the Stokes center frequency and a model is developed to predict its performance. Moreover the rate of change of the Stokes center frequency with temperature allows for precise measurements of the thermo-optic coefficient of diamond, and also shines light on the temperature-dependent average phonon frequency of the material. Furthermore, when pumped by single mode lasers, we study the periodic narrowing of the single-mode profile of the output laser due to double resonance which is modeled and analysed. Lastly, we demonstrate its use for high-resolution spectroscopy showing an achieved spectral resolution of 0.51~GHz, establishing its suitability for precise measurements and ion excitation, and paving the way for a scalable photonic source for quantum technology applications.