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Optical frequency standard based on a Nd:YAG laser stabilised by saturated absorption resonances in molecular iodine using second-harmonic radiation

The results of studies devoted to the development of the optical frequency standard based on a diode-pumped 1064-nm single-frequency ring Nd:YAG laser with intracavity frequency doubling are presented. The laser frequency was stabilised by saturated absorption resonances in molecular iodine at the second-harmonic frequency of the laser (at 532 nm). The saturated absorption resonances were observed in an external luminescent cell. The relative long-term frequency stability achieved in experiments was ∼6×10-15. The physical and technical factors affecting the long-term frequency stability and reproducibility are investigated.