Impurity-induced Huang–Rhys factor in beryllium δ-doped GaAs/AlAs multiple quantum wells: fractional-dimensional space approach

Abstract

This paper reports the observation of phonon sidebands in the photoluminescence spectra of Be acceptor-doped GaAs/AlAs multiple quantum wells. The intensity and energetic positions of the sideband lines are investigated experimentally for several quantum wells having various doping concentrations and photoluminescence excitation intensities. Theoretical analysis of a sideband-related lineshape, considering their energy position and impurity-induced spectra, has shown that phonon satellites can be attributed to free-electron-Be acceptor transitions involving longitudinal optical phonons of the GaAs-the host material of the studied quantum wells. The Huang-Rhys factor which determines the distribution of luminescence intensities between the phonon replicas and the main no-phonon peak was examined both experimentally and theoretically by varying the quantum well width. Thus, it has been found that this factor increases monotonically from 0.052 to 0.11 as the width of the quantum well decreases from 20 nm to 5 nm. The dependence of the Huang-Rhys factor on the width of the quantum well for a free-to-acceptor recombination was calculated applying the fractional-dimensional space approach. The proposed model adequately describes the experimentally determined dependence of the Huang-Rhys factor.

Peculiarities of Excitonic Photoluminescence in Si δ-Doped GaAs Structures

“…The excitonic line of the δ-doped sample is about 500 times more intensive than that in GaAs after removal of the δ layer. From the intensities of PL replicas, the Huang-Rhys factor S = 2I 2LO /I 1LO , where I 1LO is intensity of the first and I 2LO is intensity of the second phonon replica of e-A transition [8], respectively, was estimated. The obtained S value for the sample with a single δ-doped layer was equal to 0.03-0.034, for the sample with five δ layers it was equal to 0.03-0.039, and for the etched GaAs structure it equaled 0.04, which is in agreement with the value S = 0.05 for acceptor doped GaAs epilayer [8].…”

Radiative recombination spectra of p-type δ-doped GaAs∕AlAs multiple quantum wells near the Mott transition

“…30 This fine structure in the spectra, however, vanishes in medium and highly doped samples, possibly because of screening by free carriers, which becomes more effective with increased acceptor concentration. 3͒.…”

Interfacial Polar‐Bonding‐Induced Multifunctionality of Nano‐Silicon in Mesoporous Silica

“…One may expect larger S values for the intraband transition because of a large difference in the symmetry of the initial and final states involved. [29] The one-sidedbonding model shown in Figure 4b results in a non-zero diagonal matrix element of the electron-phonon interaction, since this geometry breaks the spherical symmetry of the charge distribution. Furthermore, non-adiabatic electron-phonon interaction can also occur, in which the electron motion is coupled to the ion motion in the crystal Hamiltonian.…”