New Publication: “Sub-kilohertz laser linewidth narrowing using polarization spectroscopy”

Stabilisation of laser frequency is essential for numerous applications, including atomic clocks, laser cooling and trapping of atoms, and Bose-Einstein condensation. We have shown that polarisation spectroscopy can achieve frequency narrowing to below 1kHz.  The method is inherently tied to an absolute atomic resonance, and relatively simple compared to the more common approach of locking to an ultrastable optical cavity.

Laser transmission through an ultrastable optical cavity resonance. Frequency stabilisation feedback is via piezo only, and to current with slow and high bandwidth.

Reference: J. S. Torrance, B. M. Sparkes, L. D. Turner, R. E. Scholten, Optics Express 24, 11396 (2016) [pdf]