Abstract
We demonstrate the laser operation by an ultrasmall mode in photonic crystal (PC) and quasiperiodic photonic crystal (QPC) nanocavities fabricated into GaInAsP slab. In the former, the smallest modal volume of 0.019 μm3 =0.15 (λ/n) 3 is achieved by using a PC point-shift nanocavity. In the latter, as well as the nanocavity mode lasing, unique localization of Bragg modes arising from fractal lattices of the QPC is observed. These nanocavities are effective for the enhancement of the spontaneous emission rate (so-called Purcell effect). The time-resolved measurement shows 28 times faster spontaneous emission decay in the point-shift nanocavity.
