Description
Nuclear optical clocks and other quantum technologies require narrow-linewidth lasers with watt-level powers at specific optical frequencies. Raman lasers provide access to these otherwise difficult-to-access wavelengths while offering ultra-narrow linewidths through suppression of pump frequency noise during stimulated Raman scattering (SRS). Theory suggests that SRS exhibits a low Schawlow–Townes limited linewidth, facilitating an 8 order of magnitude intrinsic linewidth narrowing[1]. Our group has demonstrated a robust monolithic bulk-crystal Raman laser with a kHz-level linewidth at 15 mW output power[2]. Here, we investigate optimisation of this architecture to match the wavelength, power and frequency-noise requirements of quantum applications, using the 1187 nm wavelength required for nuclear optical clocks[3].
We report a doubly resonant, YVO$_4$-based monolithic Raman laser alongside a first-principles numerical model of SRS frequency-noise transfer mechanisms. The pump laser is selected for the target Raman output wavelength while minimising frequency-noise transfer to the Stokes field, and cavity coatings are designed to increase conversion efficiency and output power towards the watt level. The model incorporates cavity, pump and Raman parameters to determine which physical mechanisms and design parameters dominate observed frequency noise. Experimental measurements of output power, relative-intensity-noise and frequency-noise spectra are compared with the model to assess its predictive capability and identify parameters for further optimisation.
The optimised architecture targets sub-Hz intrinsic linewidth, sub-kHz integrated linewidth and hundreds of milliwatts output power while maintaining robust, mode-hop-free operation at an application-relevant wavelength. By combining experimental characterisation with a physically explicit noise-transfer model, this work aims to establish design requirements for a high-power, ultra-narrow-linewidth monolithic Raman laser for quantum applications requiring long-term frequency stability.
References
[1] Pahlavani et al., APL Photonics 10, 076107 (2025).
[2] Davis et al., Opt. Lett. (2026), to be published.
[3] Fortier et al., Optica 13, 143–163 (2026).
| I am the presenting author | No |
|---|---|
| If you are not the presenting author, please give the presenting author's name: | Johannes Lilischkis |