InP-on-SOI electrically injected nanolaser diodes (Conference Presentation)

The development of energy-efficient ultra-compact nanolaser diodes integrated in a Silicon photonic platform is of paramount importance for the deployment of optical interconnects for intra-chip communications. In this work, we present our results on InP-based electrically injected photonic crystal (PhC) nanolaser integrated on a SOI waveguide circuitry. The lasers emit at room temperature in a continuous wave regime at 1560nm and exhibit thresholds of 0.1mA at 1V. We measure more than 100μW of light coupled into the SOI waveguides giving a wall-plug efficiency greater than 10%.The principle of the lasers relies on the use of a 1D PhC nanocavity made of InP-based materials positioned on top of a SOI waveguide to enable evanescent wave coupling. More in details, the laser cavity is a 650nm-wide rib waveguide drilled with a single row of equally sized holes (radius~100nm). The distance between the holes is varied to obtain Q-factors larger than 106 for a structure fully encapsulated in silica with material volume of the order of the cubic wavelength. Vertically, the InP heterostructure is a 450nm thick NIP junction embedding 5 strained InGaAsP quantum wells emitting at 1.53μm. By smartly positioning the metallic contacts, this configuration enables the efficient electrical injection of electron-holes pairs within the cavity without inducing optical losses which led us to demonstrate the laser emission coupled ta a Si waveguide.