Size distribution in self-assembled InAs quantum dots on GaAs (001) for intermediate InAs coverage

Near-field spectroscopy of bimodal size distribution of InAs∕AlGaAs single quantum dots

“…2(b) and (c) are the characteristic fingerprints of the bimodal size distributions of single QDs, obtained in far-field PL experiments on the samples having various QD thickness. 4,5,6,7,8,9,10 Note that the reported energy interval between doublet-like features of far-field PL spectra due to the bimodal-sized QDs was about several tens meV, 5,6,7 as similarly observed in our experiment. Each PL spectrum, which can be fitted into three groups by Gaussian functions as in Figs.…”

Evolution of bimodal size-distribution on InAs coverage variation in as-grown InAs/GaAs quantum-dot heterostructures

“…Lee et al [12] reported that a double-peak PL spectrum observed in in situ annealed InAs QD samples contrasted with a single peak emission in as-grown one, and the QD size bifurcated during annealing. In addition, a strong dependence on the QD size-distribution on the growth temperature assisting the carrier transfer mechanism was given by Kissel et al [13]. A few anomalous behaviors associated with modes of size-distribution in PL spectra still remain as points of issue, and the thermal redistribution of photocarriers has been discussed as one of the dominant mechanisms [11][12][13][14][15][16][17][18].…”

“…By virtue of unique zerodimensional features and strong confinement of the carrier wave functions in QDs, the structures have emerged as scientifically important systems not only in device applications but also in fundamental studies. Although a number of efforts have been made on (InGa)As-based QDs in order to clarify the formation mechanism and the related characteristics by using a variety of theoretical and experimental approaches so far [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], unusual behaviors associated with the QD size-distribution are still rather ambiguous and unsettled. Previously, a number of research groups have presented some discussions on distinctive behaviors that appeared in photoluminescence (PL) spectra of QD ensembles with bimodal or multimodal size-distribution.…”

Influence of InAs Coverage on Transition of Size Distribution and Optical Properties of InAs Quantum Dots

“…For higher temperatures, the FWHM of the PL increases as a consequence of electron-phonon scattering, which becomes dominant. As reported in some studies conducive to the unusual temperature-dependent PL spectra in various (InGa)As QD ensembles [11,[18][19][20][21][22], this abnormal temperature behavior may possibly be due to thermally activated carrier redistribution between adjacent QDs with different sizes with the wetting layer serving as a carrier transfer channel.…”