We investigate a mode gap confined dielectric band laser via a 1-D photonic crystal (PhC) nanobeam (NB) nanocavity with lattice gradually shifted PhC mirror. Owing to different modal symmetries, different zeroth-order dielectric mode properties, including quality (<i>Q</i>) factors, mode volumes, lasing thresholds, and slope efficiencies, in nanocavities with two different cavity sizes are investigated. In experiments, single-mode lasing from dielectric bands with low effective lasing thresholds is obtained. Rising of the high-order modes is also observed when we increase the PhC mirror periods for high Q factor of the zeroth-order dielectric mode. In addition, we observe the bonding and antibonding modes in beamwidth mismatched coupled NB nanocavities and switch the dominant lasing mode via spatially nonuniform carrier injection.
© 2012 IEEE
Po-Tsung Lee, Tsan-Wen Lu, and Li-Hsun Chiu, "Dielectric-Band Photonic Crystal Nanobeam Lasers," J. Lightwave Technol. 31, 36-42 (2013)