An integrable all-silicon slotted photonic crystal Raman laser

Abstract

The design of an integrable all-silicon Raman laser of a foot print of $\sim 7$ $\mu$ m is proposed based on a slotted photonic crystal nanocavity. The slot has been considered to be made of a silicon nanocrystal to encash its giant Raman gain coefficient, along with the tight spatial and temporal confinement of light in the slot, exhibiting a lasing efficiency of $\sim 17.8$ % at a wavelength of 1552 nm. Simulations depict that the device requires a very small optical threshold power of the order of 0.5 $\mu$ W. Tolerances to the fabrication imperfections have also been evaluated, which explores that the device performance is tolerant up to a 6% random deviation in structural parameters like radius and in-plane positions of the holes. It has also been seen through simulations that the submicrowatt threshold is maintained even for a large deterioration of over 30% in the Q-factors and modal volumes, which reassures the realization feasibility of the device.