Low Q-factor BIC resonance and its application for sensors

Abstract

Silicon-on-chip lasers and photodetectors with novel functionalities are highly attractive not only for communication applications but also for various sensing applications. In this talk, recent results on such silicon-on-chip devices will be reported, which are based on hybrid III-V on silicon approach as well as benefiting from nanophotonic structures enabling a phenomenon known as bound-states in the continuum (BIC). The devices for discussions include energy-efficient ultra-fast silicon-on-chip lasers (Figs. 1a and 1b) [1, 2], a wavelength-selective silicon-on-chip photodetector (Fig. 1c) [3], an all-silicon IR photodetector with absorption efficiency close to 100% which is based on coherent perfect absorption [4], the first silicon-on-chip laser based 1D BIC structure with ultrahigh-speed potential (Fig. 1d), and the first silicon-on-chip laser based on asymmetric BIC structure with a potential for high-power single-mode output. Their potentials in several applications will be discussed, including chip-level optical interconnects, optical links for large datacenters and 5G fronthaul interconnects, photonics-based lab-on-a-chip sensor applications as a photonic engine and a spectrometer, LiDAR applications as a high-power source and a time-of-flight sensor, and CMOS-image sensors in near-IR or IR wavelength ranges.