Greater than one billion Q factor for on-chip microresonators
Lue Wu, Heming Wang, Qi‐Fan Yang, Qing-Xin Ji, Boqiang Shen, Chengying Bao, Maodong Gao, Kerry J. Vahala
Abstract
High optical quality (Q) factors are critically important in optical microcavities, where performance in applications spanning nonlinear optics to cavity quantum electrodynamics is determined. Here, a record Q factor of over 1.1 billion is demonstrated for on-chip optical resonators. Using silica whispering-gallery resonators on silicon, Q-factor data is measured over wavelengths spanning the C/L bands (100 nm) and for a range of resonator sizes and mode families. A record low sub-milliwatt parametric oscillation threshold is also measured in 9 GHz free-spectral-range devices. The results show the potential for thermal silica on silicon as a resonator material.