Abstract

For the ultimate thresholdless laser, one needs to find a resonant cavity that is both small and lossless. The concept of photonic bandgap is best suited for these purposes because they provide us with means to realize wavelength-scale cavities having high Q-factors. We have argued that it would be advantageous to use a cavity mode that is inherently nondegenerate since natural and efficient coupling with that sole mode is expected. One example of this genuine nondegenerate mode is the monopole mode. If one modifies the six nearest holes, this nondegenerate monopole mode can be pulled down into the photonic band gap from the air band of a 2D slab triangular lattice. We demonstrated the 2-D triangular PBG laser working in this monopole mode by optical pumping [1]. It is confirmed from the computer simulation that the introduction of a small post in the middle of the resonator does not introduce significant optical losses and therefore does not degrade the quality factor of the cavity appreciably. In other words, this middle post can be used as a wire through which electrical current can be supplied. Experimental demonstration of electrically-driven ultra-small lasers will be discussed.

© 2004 Optical Society of America