  A photonic crystal (PhC) nanocavity formed in an optically very thick slab
can support reasonably high-Q modes for lasing. Experimentally, we demonstrate
room-temperature pulsed lasing operation from the PhC dipole mode emitting at
1324 nm, which is fabricated in an InGaAsP slab with thickness (T) of 606 nm.
Numerical simulation reveals that, when T > 800 nm, over 90% of the laser
output power couples to the PhC slab modes, suggesting a new route towards an
efficient in-plane laser for photonic integrated circuits.
