Weijia Li

Designed measurement setup, implemented DSP algorithms, and performed data analysis to demonstrate record 200 Gbps IM/DD transmission over 80 km in the O-band using an InP EML with sub 1-Vpp driving swing, achieving BER below the 20% overhead SD-FEC threshold.

Developed and implemented a heterodyne measurement system replacing a $1M Lightwave Component Analyzer, maintaining test accuracy for high-speed photodiodes up to 110 GHz while significantly reducing cost

1. Designed a SiN-Si dual-layer Vernier micro-ring reflector for hybrid external cavity lasers, covering full-stack development from device/circuit/system simulation and layout to tape-out at ANT and AMF (MPW) foundries 2. Expanded the wavelength tuning range of hybrid ECLs through a self-interferometer configuration, and reduced two-photon absorption loss via adiabatic waveguide widening in the micro-ring, contributing to a granted US patent (US12548978B2, FONEX Data Systems Inc., 2026)

1. Demonstrated IMDD transmission at 300 Gbps/λ using a BTO-based MZM, implementing DSP algorithms including nonlinear compensation, and probabilistic shaping (results published as an OFC 2023 Post-Deadline Paper) 2. Analyzed system power efficiency with and without RF driver, identifying key contributors to energy consumption in next-generation beyond-200-Gbps/λ transceiver designs

1. Designed and analyzed traveling-wave Mach-Zehnder modulators (TWMZM) with interleaved L-shape and lateral PN junctions targeting AIM Photonics PDK, and characterized existing PDK components 2. Delivered internal technical reports supporting foundry interface and PDK development workflows

1. Built and automated a test setup for insertion loss and group delay characterization of silicon photonic devices (PSR, SSC), using a lightwave component analyzer (LCA). 2. Identified anomalous insertion loss in spot-size converter (SSC) structures through systematic TE/TM mode analysis, providing measurement evidence that pointed to a potential foundry fabrication defect.