Heterogeneous integration of O-band GaAs QD-on-SiN Fabry-Pérot laser with observed mode-locking

We demonstrate an O-band Fabry-Pérot laser through the heterogeneous integration of a GaAs-based quantum dot optical amplifier onto a passive silicon nitride cavity using micro-transfer printing. The laser shows an ultra-low threshold current of 20mA at 18°C and can deliver nearly 0.4mW of single-side waveguide-coupled power. The spectral peak can be tuned from 1296nm to 1334nm as the temperature increases from 10°C to 50°C. Mode-locking is achieved with an injection current of 80mA and a saturable absorption voltage of -0.6V, generating a clear RF beat note at 28.6GHz with a signal-to-noise ratio of 20dB.