Room temperature photonic crystal band-edge lasing from nanopillar array on GaN patterned by nanosphere lithography

摘要

An ordered GaN nanopillar array fabricated by nanosphere lithography exhibited room temperature photopumped lasing via the photonic crystal band-edge effect. With a monolayer of self-assembled nanospheres as hard mask, the ordered pattern was transferred to the sample to form nanopillars by inductively coupled plasma dry etch. Under pulsed optical excitation, room temperature lasing with a low lasing threshold of 30 mJ/cm~2 was achieved. The dominant lasing peak, centered at 415.6 nm, corresponds to a band-edge mode at the Γ-point of the band diagram. A Q factor in the range of 600-700, and spontaneous emission coupling factor of 0.021 were evaluated.