Transient luminescence of dense InAs/GaAs quantum dot arrays

InAs Quantum Dots in Symmetric InGaAs/GaAs Quantum Wells

“…Thus to modeling the dependence of the ground state PL intensity versus temperature the simple assumption is applied: the carriers are considered to behave as excitons or correlated electron-hole pairs. This assumption is a common feature of most exiting models [15][16][17][18]. The motivation of the choosing this approach in this paper will be clear from presented esperimental results as well.…”

“…Several comments deal with the experimental base for such simplifications are discussed below. Here the radiative lifetime in QDs ( RQD τ ) is assumed to be constant with T as expected theoretically for strong confinement in three dimensions [15][16][17][18]. The radiative recombination rate in InGaAS/GaAs QWs ( RQW τ ), as was shown in [22], is controled mainly by nonradiative recombination processes at the T≥100K.…”

“…One of the best methods of manipulating the InAs QD density and sizes inside of QWs related to controlling the QD growth temperatures [3,[12][13][14][15]. But even for the optimal QD growth parameters and capping/buffer layer compositions, the InAs QD structures are characterized by photoluminescence (PL) inhomogeneity along the wafers [16][17][18][19].…”

“…A decrease in the FWHM, together with a red shift of the emission wavelength were explained by the re-localization of carriers between dots caused by their inhomogeneous sizes. A set of theoretical works has been devoted to these questions, which described the carrier dynamics in QD systems using a rate equation model [13][14][15][16][17][18][19].…”

“…For laser or photodiode applications the surface density of QDs has to be high, but for single-QD devices the QD density has to be low. As a result, there is an extensive effort to manipulate and control the position, size, shape and density of QDs [13][14][15][16][17][18][19].…”