Microtoroids are small, ring-shaped structures typically made of glass or other materials with a high refractive index. They are commonly used in photonics research as a platform for studying light-matter interactions, such as in microcavity quantum electrodynamics and nonlinear optics. Microtoroids have unique optical properties due to their high-quality factor (Q-factor) resonance modes, allowing them to confine and manipulate light at the nanoscale. Research in this area often focuses on applications such as ultra-sensitive sensors, on-chip optical communication devices, and quantum information processing.