2015/09/09 by Jintian Lin, Lin, Jintian, Yingxin Xu +13
Engineering · Physics and Astronomy · #Advanced Fiber Laser Technologies #FOS: Physical sciences #Optics (physics.optics) #Photonic and Optical Devices #Photorefractive and Nonlinear Optics
paper · pdf · doi:10.48550/arxiv.1509.02607
openalex publication_date 2015/09/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Nonlinear optical processes in whispering gallery mode (WGM) microresonators have attracted much attention. Owing to the strong confinement of light in a small volume, a WGM microresonator can dramatically boost the strength of light field, thereby promoting the nonlinear interaction between the light and the resonator material. However, realization of efficient nonlinear parametric process in microresonators is a challenging issue. The major difficulty is to simultaneously ensure the phase matching condition and a coherent multiple resonance condition for all the waves participating in the nonlinear conversion process. Here, we demonstrate highly efficient second harmonic generation (SHG) in an on-chip lithium niobate microresonator fabricated by femtosecond laser direct writing. We overcome the difficulty of double resonance for the phase matched pump and second harmonic waves by selectively exciting high order modes in the fabricated thin-disk microresonator. Our technique opens opportunities for integrated classical and quantum photonic applications.