Monolithically Integrated Ultralow Threshold Topological Corner State Nanolasers on Silicon

Monolithic integration of energy-efficient and ultracompact light sources on an industry-standard Si platform has emerged as a promising technology to realize fully integrated Si-based photonic integrated circuits. Recently, semiconductor topological lasers using topologically protected defect modes have received extensive investigation, owing to their unique merits, including robustness against structural imperfections and disorders. However, due to the significant material dissimilarities between Si and III-V materials, previous demonstrations of semiconductor topological lasers have been limited to their native substrates. Here, we experimentally report ultralow threshold, continuous-wave, optically pumped, single-mode, InAs/GaAs quantum dot, topological corner state nanolasers monolithically integrated on a CMOS-compatible Si (001) substrate. Our results represent a new route toward ultracompact and high-performance integrated nanoscale light sources for Si photonics and enable promising applications for topological photonics