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تسجيل مستخدم جديدThe magnetopolaron effect in light reflection and absorption by a wide quantum
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Light reflection and absorption spectra by a semiconductor quantum well (QW), which width is comparable to a light wave length of stimulating radiation, are calculated. A resonance with two close located exited levels is considered. These levels can arise due to splitting of an energy level of an electron-hole pair (EHP) due to magnetopolaron effect, if the QW is in a quantizing magnetic field directed perpendicularly to the QW plane. It is shown that unlike a case of narrow QWs light reflection and absorption depend on a QW width $d$. The theory is applicable at any ratio of radiative and non-radiative broadenings of electronic excitations.
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Light reflection and absorption spectra by a semiconductor quantum well (QW) , which width is comparable to a light wave length of stimulating radiation, are calculated. A resonance with two close located exited levels is considered. These levels can
arise due to splitting of an energy level of an electron-hole pair (EHP) due to magnetopolaron effect, if the QW is in a quantizing magnetic field directed perpendicularly to the QW plane. It is shown that unlike a case of narrow QWs light reflection and absorption depend on a QW width $d$. The theory is applicable at any ratio of radiative and non-radiative broadenings of electronic excitations.
We investigate the time dependent thermal relaxation of a two-dimensional electron system in the fractional quantum Hall regime where ballistic phonons are used to heat up the system to a non-equilibrium temperature. The thermal relaxation of a 2DES
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Tunnel spectroscopy is used to probe the electronic structure in GaAs quantum well of resonant tunnel junction over wide range of energies and magnetic fields normal to layers. Spin degenerated high Landau levels ($N=2div7$) are found to be drastical
ly renormalised near energies when the longitudinal optical-phonon ($hbaromega_{LO}$) and cyclotron energy ($hbaromega_{C}$) are satisfied condition $hbaromega_{LO}=mhbaromega_{C}$, where $m=1,2,3$. This renormalisation is attributed to formation of resonant magnetopolarons, i.e. mixing of high index Landau levels by strong interaction of electrons at Landau level states with LO-phonons.
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eld dependence of $sigma_{xx}$ exhibits three sets of oscillations related to the transitions between Landau levels in symmetric and antisymmetric subbands and with the transitions occurring owing to the Zeeman splitting of these subbands. The analysis of the frequency dependence of the ac conductivity and the $sigma_1 / sigma_2$ ratio demonstrates that the conductivity at the minima of oscillations is determined by the hopping mechanism.
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