Atomic clocks based on Coherent Population Trapping (CPT) in cesium [1] or other sensors based on CPT require the development of specific low noise laser sources at resonant wavelengths. For instance, the double lambda scheme for CPT probed by lin ⊥ lin laser beams, which has been shown to create Raman–Ramsey fringes with a larger contrast than the usual simple lambda scheme in [2], requires the availability of two cross-linearly polarized frequencies at 852 nm with a low beat note phase noise and a low intensity noise. One way to generate these two frequencies with low amplitude and phase noises is to build a dual-frequency VECSEL (Vertical External Cavity Surface Emitting Laser) [3]. In this talk we will present our efforts to understand the physical origin of the laser amplitude and phase noises [4], and the developments that we have made to reduce these noises to the levels necessary to achieve a relative clock stability of 10-13 at 1 s integration time.

Date Published: 9 March 2020
PDF
Proc. SPIE 11296, Optical, Opto-Atomic, and Entanglement-Enhanced Precision Metrology II, 112960A (9 March 2020); doi: 10.1117/12.2545583

Published in SPIE Proceedings Vol. 11296:
Optical, Opto-Atomic, and Entanglement-Enhanced Precision Metrology II
Selim M. Shahriar; Jacob Scheuer, Editor(s)