Spectrally resolved spontaneous emission patterns of oxide-confined vertical-cavity surface-emitting lasers

Abstract

Spectrally resolved spontaneous emission patterns of oxide-confined vertical-cavity surface-emitting lasers under the subthreshold condition were investigated. The spontaneous emission mode patterns show clear and stable Hermite-Gaussian modes and high-order Laguerre-Gaussian modes associated with a distinct spectrum. The coexistence of two sets of identical low-order Hermite-Gaussian modes with different spot sizes reveals the presence of two cavity configurations. The data on mode evolution and spot size variation reveal that the modes with larger spots are supported by the cavity with the carrier-induced aperture, and become the dominant modes above the laser threshold; the modes associated with smaller spots are considered to have been formed by the cavity with the oxidized aperture and are suppressed above the threshold. (C) 2004 American Institute of Physics.