Full text loading...
(Color online) (a) Atomic force microscope image of ring-shaped GaAs QDs. The scan area is . (b) Cross-sectional profile of a ring-shaped QD.
(Color online) PL spectra of an ensemble of ring-shaped QDs measured at (upper) and RT (lower). A fit to the RT spectrum using two Gaussian functions is also shown.
(a) Emission spectra taken from the cleaved side with various excitation powers (8, 10, 12, and ) at . The inset shows a magnified spectrum at . (b) Integrated emission intensities at as a function of excitation power.
(a) Lasing spectra at 77, 125, 175, 225, 275, and . [(b) and (c)] Center energy and threshold power of the lasing as a function of temperature. The dotted line in (b) shows the temperature dependence of the GaAs band gap energy. The dotted line in (c) shows the fit according to the characteristic temperature of .
Article metrics loading...