Photonic-corral-mode quantum ring lasers investigated by laser scanning microscopy and near field microscopy

Ultralow threshold microcavity lasers are ideal candidates for high-density optical interconnect light sources. Although they have been extensively studied for the last decade, muA-level electro-pumped quantum confined lasers are still under investigation. Photonic-corral-mode quantum ring (PQR) lasers with the linewidth narrower than 0.55 generate micro-to-nano-ampere thresholds, and become ideal for CMOS-driven high-density emitter arrays for intra-chip optical interconnect as well as other applications such as displays. By using laser beam induced current technique (LBIC) technique in laser scanning microscopy (LSM) we investigated the photocurrent confinement in the laser structure. The photocurrent map gives the possibility to analyze the laser structure uniformity. The emission spectra of a PQR laser was investigated by using of microscopic optical fiber probe.