Photo-pumped lasing from low density self-assembled InGaAs/GaAs quantum dots within a high-Q vertical cavity

A high-Q cavity containing three layers of self-assembled InGaAs/GaAs quantum dots has been prepared. Emission occurs in the wavelength range 1275–1285 nm over the wafer surface. We have observed lasing thresholds in the power-in-versus-power-out characteristics, with associated changes in the angular emission profile, when the structure is optically pumped CW at 300 K. At high pump powers spectrally resolved lateral modes are seen in the emission spectra of a planar cavity and this is discussed in terms of the index change induced by the pump laser.