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High finesse fiber ring cavity for frequency stabilizaiyon of Nd:YAG laser with pound-drever-hall method

We have fabricated a high finesse fiber ring cavity with a record high finesse of 938, free-spectral range of 413 MHz, and line-width of 440 kHz, respectively. The fiber ring cavity has been successfully used for the frequency stabilization and line-width reduction of a highly-stable Nd:YAG laser at 1064 nm by employing the Pound-Drever-Hall frequency locking method. The measured short-term frequency stability of the Nd:YAG laser was on the level of 10 kHz and remained locked for long time.