Experimental investigation of slow light phenomenon in photonic crystal waveguide line defect laser

Abstract

The guide mode whose frequency locates in the band edge in photonic crystal single line defect waveguide has very low group velocity. So the confinement and gain of electromagnetic field in the band edge are strongly enhanced. Photonic crystal waveguide laser is fabricated and the slow light phenomenon is investigated. The laser is pumped by pulsed pumping light at 980nm whose duty ratio is 0.05%. The active layer in photonic crystal slab is InGaAsP multiple quantum well. Light is transimited by a photonic crystal chirp waveguide in one facet of the laser. Then the output light is coupled to a fiber and the character of laser is analysis by an optical spectrometer. It is found that single mode and multimode happens with different power of pumping light. Meanwhile the plane wave expansion and finite-difference time-domain methods are used to simulate the phenomenon of slow light. And the result of the experiment is compared with the theory which proves the slow light results in lasing oscillation.)

Silicon photonics in China

“…The group studied the delay performance of three modulation formats, nonreturn-to-zero (NRZ), return-to-zero (RZ), and differential phase-shift keying (DPSK), at different data rates in silicon microring resonators based on the thermal nonlinear effect [28][29][30][31][32]. W. Zheng's group has theoretically investigated the transmittance efficiency in various photonic crystal waveguide bends in SOI material systems, they also did some experiments on the impact of imperfect symmetry on band edge modes of a two-dimensional photonic crystal with square lattice in InP material system [33,34].…”