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arXiv · 2108.02411

Locking Multi-laser Frequencies to a Precision Wavelength Meter: Application to Cold Atoms

Junwoo Kim·Keumhyun Kim·Dowon Lee·Yongha Shin·Sungsam Kang·Jung-Ryul Kim·Youngwoon Choi·Kyungwon An·Moonjoo Lee
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Abstract

We herein report a simultaneous frequency stabilization of two 780-nm external cavity diode lasers using a precision wavelength meter (WLM). The laser lock performance is characterized by the Allan deviation measurement in which we find $\sigma_{y}=10^{-12}$ at an averaging time of 1000 s. We also obtain spectral profiles through a heterodyne spectroscopy, identifying the contribution of white and flicker noises to the laser linewidth. The frequency drift of the WLM is measured to be about 2.0(4) MHz over 36 hours. Utilizing the two lasers as a cooling and repumping field, we demonstrate a magneto-optical trap of $^{87}$Rb atoms near a high-finesse optical cavity. Our laser stabilization technique operates at broad wavelength range without a radio frequency element.

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Junwoo Kim, Keumhyun Kim, Dowon Lee, Yongha Shin, Sungsam Kang, Jung-Ryul Kim, Youngwoon Choi, Kyungwon An, Moonjoo Lee. 2021-08-05. Locking Multi-laser Frequencies to a Precision Wavelength Meter: Application to Cold Atoms. https://doi.org/10.3390/s21186255

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