We give an introduction to the feature issue composed of twelve articles on Optical...

Optical microcavities offer a promising platform for highly efficient light–matter interactions. Recently, the combination of microresonators and 2D materials in the nanoscale has further enriched the optoelectronics of microcavit

Transient thermal instability represents a significant challenge in generating soliton microcombs. Fast laser sweep can be an efficient method to mitigate thermal instability, but it requires an ultrahigh laser sweep rate for crys

Whispering gallery mode (WGM) microbubble cavities are a versatile optofluidic sensing platform owing to their hollow core geometry. To increase the light–matter interaction and, thereby, achieve higher sensitivity, thin-walled mi

Photon number-squeezed states are of significant value in fundamental quantum research and have a wide range of applications in quantum metrology. Most of their preparation mechanisms require precise control of quantum dynamics an

Semiconductor microdisk lasers have great potential as low-threshold, high-speed, and small-form-factor light sources required for photonic integrated circuits because of their high-Q factors associated with long-lived whispering

Whispering gallery mode resonators (WGMRs) have proven their advantages in terms of sensitivity and precision in various sensing applications. However, when high precision is pursued, the WGMR demands a high-quality factor usually

Exceptional points are degeneracies in the spectrum of non-Hermitian open systems where at least two eigenfrequencies and simultaneously the corresponding eigenstates of the Hamiltonian coalesce. Especially, the robust constructio

Optical ultrasonic probes, exemplified by Fabry–Perot cavities on optical fibers, have small sizes, high sensitivity, and pure optical characteristics, making them highly attractive in high-resolution ultrasonic/photoacoustic imag

Frequency engineering of whispering-gallery resonances is essential in microcavity nonlinear optics. The key is to control the frequencies of the cavity modes involved in the underlying nonlinear optical process to satisfy its ene

We experimentally demonstrate an all-pass microring resonator (MRR) based on a Y2O3 BOX germanium-on-insulator (GeOI) platform operating in the mid-IR region. The ring resonator was numerically designed to have a high quality (Q)

The per- and polyfluoroalkyl substances (PFAS) are a group of organofluorine chemicals treated as the emerging pollutants that are currently of particularly acute concern. These compounds have been employed intensively as surfacta

Self-chaotic dual-mode and tri-mode microcavity lasers have been recently proposed and demonstrated for high-speed random number generation. Here, we report the characteristics of irregular pulse packages and self-chaos operation