High-Power Micro-Transfer Printed 796 nm Fabry-Perot Laser

A recent push has been made towards the heterogeneous integration of laser sources at wavelengths around 800 nm through wafer bonding [1], [2]. However, for nonlinear applications such as microcomb generation for spectroscopy and absolute frequency referencing in atomic clocks, higher-power integrated laser sources are required. The main power limitation inherent to wafer bonded lasers is the low thermal conductivity of the silicon oxide layer between the heat-generating III-V layers and the silicon substrate, leading to thermal roll-off. To avoid this problem, the superior flexibility of micro-transfer printing can be used to directly print III-V laser sources on the silicon substrate in recesses etched in silicon nitride (SiN) photonic-integrated circuits [3], vertically aligning the III-V mode with the silicon nitride waveguide and facilitating greatly improved thermal characteristics. In this work, we show the fabrication of micro-transfer printable edge-emitting Fabry-Perot laser coupons. These coupons are successfully printed on a silicon substrate, showing high laser power (> 70 mW at 150 mA) around 795 nm without thermal roll-off.