Fabrication of InAs quantum dots in AlAs∕GaAs DBR pillar microcavities for single photon sources

We report the molecular beam epitaxy growth of low-density strain-induced InAs quantum dots (QD) embedded in an AlAs∕GaAs distributed Bragg reflector structure for a triggered photon source. By optimal selection of growth temperature, InAs deposited thickness and other experimental parameters, it is possible to grow low density (10∕μm2) InAs quantum dots with a suitable emission wavelength for a triggered photon source. The empirical formulas for the refractive indices of AlAs and GaAs materials at high temperature over a wide wavelength range are constructed by combining high resolution x-ray diffraction, dynamic optical reflectivity, and optical reflectivity spectrum techniques. Utilizing the electron-beam lithography and electron-cyclotron-resonance plasma etching techniques, a micropost microcavity with the top diameter of 0.6μm and the post height of 4.2μm has been fabricated. Narrow, spectrally limited single QD emission embedded in a micropost microcavity is observed in the photoluminescence.