Research

Optical beam steering enables optical detection and imaging in macroscopic or microscopic scales and long-range communication over free space. It underpins numerous optical applications, including LiDAR, biomedical imaging, and remote sensing. Despite the inherent speed of light, advanced applications increasingly require the ability to steer multiple beams simultaneously to increase imaging throughput, boost communication bandwidth, and control arrays qubits for scalable quantum computing. We are developing integrated acousto-optic beam steering (AOBS) systems with photonic integrated circuits to enable a scalable platform for multi-beam steering, advancing many areas of optical technologies in sensing, imaging, and quantum applications.

Ref: Li, et al., Nature (2023), Lin, et al, arXiv.2409.16511 (2025)

Photonic integrated circuits (PICs) technology that can be rapidly prototyped and readily reprogrammed will have revolutionary impacts in a wide range of photonic technologies. We are developing a technology of direct-write and rewritable photonic circuits based on a low-loss phase change material (PCM) thin film, in which complete end-to-end functional photonic circuits can be created by direct laser writing in one step without additional fabrication processes. The direct-write phase-change photonic circuit affords exceptional flexibility, allowing any part of the circuit to be erased and rewritten, facilitating rapid design modification and reprogramming. We are further advancing the technology from 2D to 3D.

Ref: Wu, et al., Science Advances (2024)

Light-matter interaction is inevitably accompanied by mechanical effects because each photon carries both linear and angular momentum—orbital and spin—that will be transferred to the matter. These optomechanical effects become very strong in nanophotonic devices because of much-enhanced field intensity and thus strong light-matter interaction. In nano-optomechanical systems (NOMS), the pronounced optomechanical effects have been exploited in highly integrated photonic devices for both classical applications, such as optical signal processing and communication, and for quantum applications, such as quantum transduction and quantum sensing.

Ref: Chen, et al., Nature Communications (2023)

Emerging 2D and quantum materials, such as graphene, black phosphorus, transition metal dichalcogenides (TMDCs), layered topological insulators, and twisted 2D systems, hold immense potential for quantum photonics. Our research focuses on generating and manipulating quantum light within these materials and integrating them with photonic and optomechanical circuits. Our ultimate goal is to develop a quantum photonic circuit system for next-generation communication and sensing applications.

Ref: Ripin, et al., Nature Nanotechnology (2023). Peng, et al., Nature Communications (2022)

IR spectroscopy can provide chemically specific information on biochemical analytes such as lipids, proteins, and nucleic acids in a nondestructive fashion by accessing their vibrational fingerprints in the mid-IR range (2-10 µm). The integration of nanoplasmonic devices with a silicon photonic platform affords a new approach for efficient light delivery by combining the high field enhancement of plasmonics and the ultra-low propagation loss of dielectric waveguides. Such a hybrid integration obviates the need for a bulky free-space optics setup and can lead to fully integrated, on-chip optical sensing systems.

Ref: Chen, et al., Nano Letter (2018)