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arXiv · 2005.09813

Polygon Coherent Modes in aWeakly Perturbed Whispering Gallery Microresonator for Efficient Second Harmonic, Optomechanic and Frequency Comb Generations

Zhiwei Fang·Sanaul Haque·Farajollahi Saeed·Haipeng Luo·Jintian Lin·Rongbo Wu·Jianhao Zhang·Zhe Wang·Min Wang·Ya Cheng·Tao Lu
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Abstract

We observe high optical quality factor (Q) polygonal and star coherent optical modes in a lithium niobate microdisk. In contrast to the previous polygon modes achieved by deformed microcavities at lower mechanical and optical Q, we adopted weak perturbation from a tapered fiber for the polygon mode formation. The resulting high intracavity optical power of the polygon modes triggers second harmonic generation at high efficiency. With the combined advantage of high mechanical Q cavity optomechanical oscillation was observed for the first time. Finally, we observe frequency microcomb generation from the polygon modes with an ultra stable taper-on-disk coupling mechanism.

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Zhiwei Fang, Sanaul Haque, Farajollahi Saeed, Haipeng Luo, Jintian Lin, Rongbo Wu, Jianhao Zhang, Zhe Wang, Min Wang, Ya Cheng, Tao Lu. 2020-05-20. Polygon Coherent Modes in aWeakly Perturbed Whispering Gallery Microresonator for Efficient Second Harmonic, Optomechanic and Frequency Comb Generations. https://doi.org/10.1103/physrevlett.125.173901

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