Widely-tunable, doubly-resonant Raman scattering on diamond in an open microcavity

Abstract

Raman lasers based on bulk diamond are a valuable resource for generating coherent light in wavelength regimes where no common laser diodes are available. Nevertheless, the widespread use of such lasers is limited by their high threshold power requirements on the order of several Watts. Using on-chip microresonators, a significant reduction of the lasing threshold by more than two orders of magnitude has been shown. However, these resonators lack a continuous tuning mechanism and, mainly due to fabrication limitations, their implementation in the visible remains elusive. Here, we propose a platform for a diamond Raman laser in the visible. The device is based on a miniaturized, open-access Fabry-Perot cavity. Our microcavity provides widely-tunable doubly-resonant enhancement of Raman scattering from high quality single-crystalline diamond. We demonstrate a >THz continuous tuning range of doubly-resonant Raman scattering, a range limited only by the reflective stopband of the mirrors. Based on the experimentally determined quality factors exceeding 300 000, our theoretical analysis suggests that, with realistic improvements, a sub-mW threshold is readily within reach. Our findings pave the way to the creation of a universal low-power frequency shifter, a potentially valuable addition to the nonlinear optics toolbox.

Diamond Integrated Quantum Nanophotonics: Spins, Photons and Phonons

“…Resonant coupling of a single NV center to an open microcavity has demonstrated enhancement of the fraction of ZPL photons to ∼ 46 % [124]. Finally, the incorporation of a diamond membrane with a small thickness gradient has demonstrated full in situ control of both the resonant frequency, and the relative frequency spacing of adjacent cavity modes [307], thus providing a platform for tunable nonlinear optics.…”

Diamond Integrated Quantum Photonics: A Review

“…Resonant coupling of a single NV center to an open microcavity has demonstrated enhancement of the fraction of ZPL photons to ∼ 46 % [122]. Finally, the incorporation of a diamond membrane with a small thickness gradient has demonstrated full in situ control of both the resonant frequency, and the relative frequency spacing of adjacent cavity modes [348], thus providing a platform for tunable nonlinear optics.…”