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By using the quantum kinetic equation for the distribution function of electrons, the expression for Ettingshausen coefficient (EC) in quantum wells with parabolic potential (QWPP) in the presence of electromagnetic wave (EMW) is obtained for electrons - confined acoustic phonons scattering. The analytic results have shown that EC depends on temperature, magnetic field, characteristic quantities of EMW and m - quantum number which is specific the confined phonons in a complicated way. The numerical results for GaAs/GaAsAl quantum wells (QW) have displayed these dependence explicitly. In particular, when m is set to zero, we achieve results for magneto – thermoelectric effect in the same QW without the confinement of acoustic phonons.

The quantum Etttingshausen e˙ect in a parabolic quantum well subjected to a constant electric field, magnetic field in the presence of laser radiation is studied by using the quantum kinetic equation method. The analytic expressions for conductivity tensors and dynamic tensors as well as the Ettingshausen coe˚cient (EC) are obtained in the case of the confined electron-confined optical phonon (COP) scattering. The EC depends on specific quantities for external field (such as magnetic field, amplitude and frequency of laser radiation), temperature of the system and quantum well length, especially quantum number m-characterizing the confinement of optical phonon (OP). When m is set to zero, we get the results corresponding to the case of unconfined OP. The analytic results are numerically evaluated and graphed for GaAs/AlGaAs parabolic quantum well. When examining the e˙ect of temperature, the EC has greater values due to the COP. Meanwhile, when quantum well length and amplitude of the laser radiation (LR) increase, the EC has greater values without the confinement of OP. Because of the approach of system to bulk semiconductor structure when the quantum well length approaches micrometer-size, the EC reaches constant. The quantum number m leads to the change of resonance peaks position within the change of the magnetic field and the frequency of LR. In addition, the EC exerts non-linear dependence on the amplitude the LR. All results indicated that the COP a˙ects not only qualitatively but also the transformation rules of the EC. It provides new insights and contributes to the orientation of research into quantum e˙ects in low-dimensional semiconductor systems (LDS).

Based on the quantum kinetic equation method, the influence of confined optical phonons and laser radiation on the Radioelectric effect in a cylindrical semiconductor quantum wire with parabolic potential subjected to a dc electric field and a linearly polarized electromagnetic wave has been theoretically studied. The obtained analytical expression of the Radioelectric field (REF) depends on frequencies and amplitudes of the external electromagnetic waves, the quantum wire parameters, the temperature of the system, and especially the quantum numbers (n and m) which characterize the phonon confinement. Numerical calculations for the GaAs/GaAsAl quantum wire show the strongly impact of the confined optical phonons as well as the laser radiation on the REF magnitude and posture. The REF also has more resonance peaks in comparison with that in case of bulk phonon.

The Nonlinear Absorption of a Strong Electromagnetic Wave in Low-dimensional Systems