This research proposal presents a novel approach to achieve ultra-low threshold continuous-wave lasing in silicon-compatible platforms by exploiting the frozen mode regime in photonic crystal waveguides. The design combines dispersion-engineered silicon waveguides supporting stationary inflection points with heterogeneous III-V quantum dot gain media to create extended optical modes with vanishing group velocity and enhanced light-matter interaction. The proposed device targets lasing thresholds below 1 µW, representing a 1000-fold reduction compared to conventional silicon Raman lasers, alongside mode volumes of ~0.5(λ/n)³ and quality factors exceeding 10⁶.
Key findings
Design of silicon photonic crystal waveguides supporting frozen mode operation with group velocity reduction factors exceeding 10³ through stationary inflection points and degenerate band edges
Development of hybrid III-V/Si heterogeneous integration architecture incorporating InAs/GaAs quantum dots as gain media with optimized evanescent coupling to frozen mode waveguides
Comprehensive theoretical framework modeling frozen mode lasing dynamics including Purcell enhancement, spontaneous emission coupling efficiency, and gain saturation effects
Target performance metrics include continuous-wave lasing threshold below 1 µW and 1000-fold improvement over state-of-the-art silicon Raman lasers
Limitations & open questions
Fabrication challenges in achieving precise dispersion engineering for stationary inflection points in silicon photonic crystals
Thermal management constraints due to energy accumulation in slow-light modes with extreme group velocity reduction
Coupling efficiency limitations between III-V quantum dot gain media and silicon frozen mode waveguides