To meet the growing demand for high-speed indoor access by multiple devices, traditional radio-frequency communications are facing increasing pressure in terms of spectrum availability and interference resilience, which has drawn significant attention to optical wireless communication (OWC). Using optical waves as carriers, OWC offers abundant bandwidth resources and strong immunity to electromagnetic interference. Existing indoor OWC systems are mainly based on visible light communication (VLC). Although VLC can simultaneously provide illumination and communication, it still faces several practical limitations, such as interference from neighboring lighting sources, performance degradation when brightness must be reduced in scenarios without lighting demand, and visual disturbance caused by uplink light emission. In contrast, near-infrared light is invisible to the human eye and can support higher transmit power while alleviating visual disturbance, making it more suitable for constructing practical indoor bidirectional communication systems. Moreover, OWC systems intended for real-world deployment must also possess capabilities such as real-time signal processing, compatibility with network protocols, link interruption recovery, and multi-user access. Therefore, the realization of an indoor multi-user near-infrared optical wireless communication system is of great research significance.

Brillouin scattering is one of the most widely applied principles in optical fiber sensing technology. It is not only used for measuring temperature and strain but has also extended to emerging fields such as substance identification, microwave frequency measurement, and photoacoustic microscopy. However, traditional Brillouin sensing is fundamentally constrained in spatiotemporal resolution by the involvement of acoustic waves. Because the phonon lifetime in silica fibers is approximately 10 ns, it is difficult for the system to resolve events within shorter time scales, resulting in a spatial resolution that is typically limited to the meter scale. Meanwhile, forward Brillouin scattering (FBS) also faces severe challenges in distributed measurement, such as the long lifetime and weak signal of acoustic waves, as well as the co-propagation of scattered waves and incident light, which makes it impossible to directly obtain position information.

This research focuses on enhancing light–matter interactions through the development of a novel hybrid microcavity that couples a circular Bragg grating (CBG) with a fiber-based Fabry–Pérot cavity (FFPC). The resulting hybrid mode offers wavelength tunability, an enhanced Purcell factor, and seamless interfacing with optical fibers. Moreover, this scheme provides a versatile platform to tailor the spatial profile of the optical field, paving the way for high-quality, mode-engineered quantum light sources.

Quantum networks connect distant quantum systems using photons as flying qubits, but different platforms operate at very different wavelengths. Trapped ions often emit ultraviolet photons, while many solid-state quantum memories work in the visible or near-infrared. A practical interface must translate photon frequency across a large gap without degrading the encoded quantum state.