[MoA4] III-Vs on Si (II)

5:00 PM - 5:30 PM JST(8:00 AM - 8:30 AM UTC)

[MoA4-02 Invited] InAs/InAlGaAs quantum dot laser on InP and Si substrates

Hui Jia¹, Jae-Seong Park¹, Jun Li¹, Kongming Liu¹, Jiajing Yuan¹, Yangqian Wang¹, Mingchu Tang¹, 〇Huiyun Liu¹ (1. University College London (UK))

We will present the recent progress in long-wavelength InAs/InAlGaAs quantum-dot (QD) lasers grown on both InP and Si substrates, enabled by a modified indium-flush technique specifically engineered to enhance dot uniformity and emission control. By incorporating a strained partial capping layer during epitaxy, we achieve markedly improved QD height distribution and reduced inhomogeneous broadening, supporting high-density multi-stack active regions essential for long-wavelength photonic integration. Seven-stack InAs/InAlGaAs QD lasers on InP exhibit state-of-the-art performance, including threshold current densities as low as 63 A/cm2 per QD layer and maximum operating temperatures up to 140°C under pulsed operation. Continuous-wave characterization highlights important thermal considerations and pathways toward further improvement. Extending this methodology, we also demonstrate electrically pumped InAs/InAlGaAs QD lasers directly grown on CMOS-compatible Si (001) substrates, using optimized InP/Si templates and dislocation filtering to mitigate defect formation. These Si-based devices achieve threshold current densities of 1.35 kA/cm2 and lasing up to 100°C, representing significant progress toward monolithic long-wavelength light sources for silicon photonics. The results position the modified indium-flush technique as a powerful and scalable approach for advancing C-/L-band QD lasers and enabling integrated photonic platforms central to next-generation communication technologies.