Effects of applied magnetic fields and hydrostatic pressure on the optical transitions in self-assembled InAs/GaAs quantum dots

Abstract

A theoretical study of the photoluminescence peak energies in InAs self-assembled quantum dots embedded in a GaAs matrix in the presence of magnetic fields applied perpendicular to the sample plane is performed. The effective mass approximation and a parabolic potential cylinder-shaped model for the InAs quantum dots are used to describe the effects of magnetic field and hydrostatic pressure on the correlated electron-hole transition energies. Theoretical results are found in quite good agreement with available experimental measurements for InAs/GaAs self-assembled quantum dots.

Optical transition in self-assembled InAs/GaAs quantum lens under high hydrostatic pressure

“…is the gap energy at T = 0 and P = 0, α is the pressure coefficient and κ and c are the temperature coefficients 35 . For the case of InAs/GaAs SAQD, the parameters used for both materials are shown in Table I.…”

“…height of the potential barrier V o = V c as a function of the pressure by dashed lines. The band offset of the strained InAs/GaAs quantum lens was taken, for the conduction (valence) band, as 54% (46%) of the total band difference 35 . It is interesting to note the decreasing of the values of the conduction energies levels with the increasing of P , in spite of the increasing of the barrier height according to Eq.…”

“…This behavior is due to the InAs energy gap dependence on P according to Eq. (2) 35,48 . In the case of Fig.…”

“…In our simulation the strain effect within the QD has been taking into account through an effective linear pressure coefficient at zero temperature which consider the built-in strain of the dot by assuming a simple two-dimensional strained layers model (see Table I and Refs. 32,35,36). The QDs considered here are within the strong confinement regime and as first approximation the excitonic effects are ignored.…”

Influence of Oscillatory Impurity Potential and Concurrent Gasping of Impurity Spread on Excitation Profile of Doped Quantum Dots

“…This happens because of the interplay between various confinement sources with impurity potentials [2]. Out of various kinds of investigations on impurity doping, control of optoelectronic properties emerges as the central theme [3][4][5][6][7][8][9][10][11][12][13][14][15]. Naturally, we find a vast literature comprising of good theoretical studies on impurity states [16][17][18][19][20][21].…”