AUTHOR=Jin Pixian , Wei  Jiao , Su  Jing , Lu Huadong , Peng  Kunchi 

TITLE=Recent progress in continuously tunable low-noise all-solid-state single-frequency continuous-wave laser based on intracavity locked etalon

JOURNAL=Frontiers in Physics

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2022.1029336

DOI=10.3389/fphy.2022.1029336

ISSN=2296-424X

ABSTRACT=All-solid-state single-frequency continuous-wave (CW) lasers have been applied in many fields of scientific research owing to their intrinsic advantages of high beam quality, low noise, narrow linewidth, and high coherence. In atom-based applications, single-frequency lasers should also be continuously tuned to precisely match their wavelengths with the transition lines of the corresponding atoms. Continuous frequency tuning of the laser is mainly achieved by continuously scanning the laser cavity length after the intracavity tuning element etalon is locked to an oscillating laser mode. However, the modulation signal necessary in current etalon locking systems will increase the noise of the continuously tunable lasers and astrict their applications in frontier scientific research in some ways. Moreover, the obtained continuous frequency tuning range with the etalon locking technique is restricted by the free spectrum range of the adopted etalon. In this paper, we systematically summarized recent progress of the continuously tunable single-frequency CW lasers, including the advanced etalon locking techniques and the tuning range expansion approach. As a result, based on the presented continuous frequency tuning techniques, the low noise and high stable all-solid-state single-frequency CW tunable lasers were successfully developed.