Laser-cavity locking utilizing beam ellipticity: accessing the 10−7 instability scale relative to cavity linewidth

article Laser-cavity locking utilizing beam ellipticity: accessing the 10−7 instability scale relative to cavity linewidth published yes Fritz R Diorico author 2E054C4C-F248-11E8-B48F-1D18A9856A870000-0002-4947-8924 Artem Zhutov author 0f02ed6a-b514-11ee-b891-8379c5f19cb7 Onur Hosten author 4C02D85E-F248-11E8-B48F-1D18A9856A870000-0002-2031-204X OnHo department Frequency-stable lasers form the back bone of precision measurements in science and technology. Such lasers typically attain their stability through frequency locking to reference cavities. State-of-the-art locking performances to date had been achieved using frequency modulation based methods, complemented with active drift cancellation systems. We demonstrate an all passive, modulation-free laser-cavity locking technique (squash locking) that utilizes changes in spatial beam ellipticity for error signal generation, and a coherent polarization post-selection for noise resilience. By comparing two identically built proof-of-principle systems, we show a frequency locking instability of 5×10−7 relative to the cavity linewidth at 10 s averaging. The results surpass the demonstrated performances of methods engineered over the last five decades, potentially enabling an advancement in the precision control of lasers, while creating avenues for bridging the performance gaps between industrial grade lasers with scientific ones due to the afforded simplicity and scalability. https://research-explorer.ista.ac.at/download/14802/14824/2023_Optica_Diorico.pdf application/pdfno Optica Publishing Group2024 eng Atomic and Molecular Physicsand OpticsElectronicOptical and Magnetic Materials Optica 2334-2536 00120281700000410.1364/optica.507451 11126-31 F.R. Diorico, A. Zhutov, O. Hosten, Optica 11 (2024) 26–31. F. R. Diorico, A. Zhutov, and O. Hosten, “Laser-cavity locking utilizing beam ellipticity: accessing the 10−7 instability scale relative to cavity linewidth,” Optica, vol. 11, no. 1. Optica Publishing Group, pp. 26–31, 2024. Diorico FR, Zhutov A, Hosten O. 2024. Laser-cavity locking utilizing beam ellipticity: accessing the 10−7 instability scale relative to cavity linewidth. Optica. 11(1), 26–31. Diorico, Fritz R, Artem Zhutov, and Onur Hosten. “Laser-Cavity Locking Utilizing Beam Ellipticity: Accessing the 10−7 Instability Scale Relative to Cavity Linewidth.” Optica. Optica Publishing Group, 2024. <a href="https://doi.org/10.1364/optica.507451">https://doi.org/10.1364/optica.507451</a>. Diorico FR, Zhutov A, Hosten O. Laser-cavity locking utilizing beam ellipticity: accessing the 10−7 instability scale relative to cavity linewidth. Optica. 2024;11(1):26-31. doi:<a href="https://doi.org/10.1364/optica.507451">10.1364/optica.507451</a> Diorico, Fritz R., et al. “Laser-Cavity Locking Utilizing Beam Ellipticity: Accessing the 10−7 Instability Scale Relative to Cavity Linewidth.” Optica, vol. 11, no. 1, Optica Publishing Group, 2024, pp. 26–31, doi:<a href="https://doi.org/10.1364/optica.507451">10.1364/optica.507451</a>. Diorico, F. R., Zhutov, A., & Hosten, O. (2024). Laser-cavity locking utilizing beam ellipticity: accessing the 10−7 instability scale relative to cavity linewidth. Optica. Optica Publishing Group. <a href="https://doi.org/10.1364/optica.507451">https://doi.org/10.1364/optica.507451</a> 148022024-01-15T10:25:38Z2026-07-08T08:25:12Z