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By using a quantum kinetic equation for electrons, we studied magneto - thermoelectric effects in the doped semiconductor superlattice (DSSL) under the influence of electromagnetic waves (EMW). In case of the electron - acoustic phonon interaction, we have also figured out analytical expressions of the Ettingshausen coefficient (EC) in DSSL. These expressions are quite different from those which were obtained in the case of bulk semiconductors. The results are numerically calculated for the GaAs:Be/ GaAs:Si DSSL; we found that the EC depends on the characteristic parameters of EMW, temperature and the characteristic parameters of DSSL. The results are consistent with recently experimental observations but the EC is different from that in the bulk semiconductors or bismuth. In addition, the impact of the EMW on the Ettingshausen effect was also discovered. These are latest results which have been studied in terms of Ettingshausen effect in DSSL.

We calculated analytic expressions for the absorption coefficient (ACF) of a weak electromagnetic wave (EMW) by confined electrons in cylindrical quantum wires (CQW) in the presence of laser radiation by using the quantum kinetic equation for electrons in the case of electron-optical phonon scattering. The ACF of a weak EMW depends on the intensity E 01 and frequency Ω 1 of the external laser radiation (E 1 = E 01 sin(Ω 1 t + ϕ 1)); the intensity E 02 and frequency Ω 2 of the weak EMW (E 2 = E 02 sin(Ω 2 t)), the temperature T of the system and the radius R of CQW. Then, the analytic results are numerically calculated and discussed for GaAs/GaAsAl CQW. The numerical results show that the ACF of a weak EMW in a CQW can have negative values. So, in the presence of laser radiation, under proper conditions, the weak EMW is increased. This is different from the similar problem in bulk semiconductors and from the case of the absence of laser radiation.

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Based on the quantum kinetic equation method, the quantum Ettingshausen effect has been theoretically studied under the influence of confined acoustic phonon in a cylindrical quantum wire (CQW) with infinite potential in the presence of a strong electromagnetic wave. We considered a quantum wire in the presence of a constant electric field, a magnetic field, an electromagnetic wave (EMW) with an assumption that electron – confined acoustic phonon (CAP) scattering is essential. Analytical results obtained show that the EC depends on the amplitude and the frequency of the EMW in a non-linear way. Besides, the impact of phonon confinement on the above effect characterized by m-quantum number in the expression of the EC. The theoretical results have been numerically calculated for the GaAS/AlGaAs cylindrical quantum wire model. The obtained results show that the phonon confinement contributes to the EC quantitatively and qualitatively. On the other hand m is set to zero, the result obtained is similar to the case of unconfined phonon. Furthermore, by considering the quantum size effect, the values of the EC increases, the position of the magnetic-phonon resonance peak changes, and the number of peak resonant peak increases while the radius of quantum wire declines. These obtained results are different from bulk semiconductor and unconfined phonon case which donates to the theory of the Ettingshausen effect in low-dimensional semiconductor systems.

Based on the quantum kinetic equation for electrons, we have theoretically studied the influence of a Strong Electromagnetic Wave on the Ettingshausen Effect (EC) in a rectangular quantum wire with an infinite potential (RQWIP). We obtain the analytic expressions for the kinetic tensor as well as the Ettingshausen coefficient in the rectangular quantum wire with an infinite potential with the dependence on B and Ω…… The results are numerically evaluated and graphed for GaAs/GaAs:Al quantum wire. We survey the electrical and thermal conductivity tensor depend on Electromagnetic Wave frequency and temperature. The results give us appearance of the Shubnikov–de Haas oscillations when we survey the dependence of Ettingshausen coefficient on the magnetic field. Then, we realize that as the temperature increases, the Ettingshausen coefficient decreases. This shows that the Electromagnetic Wave have a clear impact on the effects. These are latest results which have been studied in terms of Ettingshausen effect in rectangular quantum wire.

Abstract-The nonlinear absorption of a strong electromagnetic wave caused by electrons confined in cylindrical quantum wires is theoretically studied by using the quantum kinetic equation for electrons. An analytic expression of the nonlinear absorption coefficient of a strong electromagnetic wave caused by electrons confined in a cylindrical quantum wire with a parabolic potential for electron-optical phonon scattering is obtained. The dependence of the nonlinear absorption coefficient on the intensity E 0 and the frequency Ω of the external strong electromagnetic wave, the temperature T of the system and the radius R of the wires is strong and nonlinear. Analytic expression is numerically calculated and discussed for a GaAs/GaAsAl quantum wire. The results are compared with those for normal bulk semiconductors and quantum wells to show the differences.