Magneto – thermoelectric effects in quantum well in the presence of electromagnetic wave

Abstract

Abstract:We have studied magneto-thermoelectric effects in quantum well in the presence of electromagnetic wave. The analytic expression for Ettingshausen coefficient (EC) in the Quantum Well with parabolic potential (QWPP) in the presence of Electromagnetic wave (EMW) is calculated by using the quantum kinetic equation for electrons. The dependence of EC on the frequency, the amplitude of EMW, the Quantum Well parameters and the temperature are obtained. The results are numerically calculated, plotted, and discussed for GaAs/GaAsAl Quantum Well to clearly show the dependence of EC on above parameters and the results in this case are compared with the case in the bulk semiconductors. We realize that as the temperature increases, the EC decreases. The results show appearance of the Shubnikov-de Haas (SdH) oscillations when we survey the dependence of EC on the magnetic field.

The Calculation of the Ettingshausen Coefficient in Quantum Wells under the Influence of Confined Phonons (for Electron – confined Optical Phonon Scattering)

“…The graph displayed clearly that the EC has negative value in both case with and without confinement of OP. This is contrary to published results of the EC in the same QW with unconfined OP [4]. The cause of this difference is the direction of the magnetic field.…”

“…By using quantum kinetic equation method, we have found out the analytic expressions for the conductivity tensors and the EC in QW of GaAs/GaAsAl under the influence of confined OP. Due to significant contribution of the confined OP, theoretical results are different from the previous researches for Ettingshausen effect in QW [4,5]. The increase of confinement effect of OP impacts the resonant condition in QW under the influence of external field and leads to the decrease of the EC.…”

“…Model of QW used is put into a parabolic potential with confined frequency z  [4]. So, motion of the electrons is free in the x-y plane.…”

“…Due to the confinement effect, the movement of electron and phonon is severely limited. This leads to changes in characteristics of quantum effects appeared in low-dimensional semiconductor systems (LDS), in particular two-dimensional systems [1][2][3][4][5]. ________  Corresponding author.…”

“…The Ettingshausen effect has been studied in semiconductor [6] and quantum wells [4,5]. In [4,5], properties of this magneto-thermoelectric effect are different from bulk semiconductor [6] due to the confinement of the electrons. However, the confinement of phonons, in particular OP, has not been interested yet.…”