Controllable lasing behavior enabled by compound dielectric waveguide grating structures

Abstract

The photonic density of states (PDOS) is one of the key physical quantities governing the lasing behavior for photonic band-edge lasers. The PDOS is conventionally altered by exploiting the high-Q band-edge mode within a device, which is typically achieved by increasing the contrast of periodic refractive index variation (Δn) or increasing the periodic number of the photonic crystals. In this paper, we propose a different approach to achieve a high-Q band edge mode within an active compound dielectric waveguide grating (CWDG). We demonstrate that the lasing threshold and intensity can be flexibly tuned by changing the filling factors of the CWDG. This design can effectively improve the performance of electrically pumped photonic band-edge lasers.