Photonic Crystal Lasers

Abstract

The size of the smallest possible laser has been steadily approaching the physical limit of ~(λ/2n) 3 . We have witnessed the series of evolution of the small lasers over a few decades, from the 1D VCSEL to the 2D photonic crystal laser and back to the 1D ladder-type nanobeam laser. Throughout these developments, the photonic crystal helped us greatly by providing the conceptual platform of effective photon confinement. The smallest mode volume achievable from the 1D photonic crystal laser is ~10(λ/n) 3 . The mode volume of the 2D photonic crystal is ~1(λ/n) 3 , about an order of magnitude smaller. The size of the 1D nanobeam laser is found to be slightly smaller than those of 2D photonic crystal lasers. For the practical nanolaser, however, critical issues related to electrical pumping still need to be answered in a more convincing manner. © 2012 Elsevier Inc..