Optical properties of arrays of hexagonal GaN microdisks acting as whispering-gallery-mode-type optical microcavities.

The optical properties of arrays of hexagonal GaN microdisks, which potentially act as whispering-gallery-mode-type optical microcavities, were investigated. The arrays were fabricated from a GaN film using a top-down process, and the side lengths and height of the hexagonal GaN microdisks were approximately 1.5 and 500 nm, respectively. The microdisk arrays exhibited optically pumped lasing actions. The estimated lasing intensities which were obtained from one microdisk in the arrays were related to the period of the arrays. We discuss the optical properties of the microdisk arrays in view of experimental results and numerical analyses obtained using a two-dimensional finite-difference time-domain method. [ABSTRACT FROM AUTHOR]