ترغب بنشر مسار تعليمي؟ اضغط هنا

Wave Functions and Energies of Magnetopolarons in Semiconductor Quantum Wells

312   0   0.0 ( 0 )
 نشر من قبل Stanislav Pavlov
 تاريخ النشر 2004
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

The classification of magnetopolarons in semiconductor quantum wells (QW) is represented. Magnetopolarons appear due to the Johnson - Larsen effect. The wave functions of usual and combined magnetopolarons are obtained by the diodanalization of the Schrodinger equation.

قيم البحث

اقرأ أيضاً

Experimental and theoretical studies of all-optical spin pump and probe of resident electrons in CdTe/(Cd,Mg)Te semiconductor quantum wells are reported. A two-color Hanle-MOKE technique (based on continuous-wave excitation) and time-resolved Kerr ro tation in the regime of resonant spin amplification (based on pulsed excitation) provide a complementary measure of electron spin relaxation time. Influence of electron localization on long-lived spin coherence is examined by means of spectral and temperature dependencies. Various scenarios of spin polarization generation (via the trion and exciton states) are analyzed and difference between continuous-wave and pulsed excitations is considered. Effects related to inhomogeneous distribution of $g$-factor and anisotropic spin relaxation time on measured quantities are discussed.
We show that free-carrier (Drude) absorption of both polarized and unpolarized terahertz radiation in quantum well (QW) structures causes an electric photocurrent in the presence of an in-plane magnetic field. Experimental and theoretical analysis ev idences that the observed photocurrents are spin-dependent and related to the gyrotropy of the QWs. Microscopic models for the photogalvanic effects in QWs based on asymmetry of photoexcitation and relaxation processes are proposed. In most of the investigated structures the observed magneto-induced photocurrents are caused by spin-dependent relaxation of non-equilibrium carriers.
Using three-pulse four-wave-mixing femtosecond spectroscopy, we excite a non-radiative coherence between the discrete Landau levels of an undoped quantum well and study its dynamics. We observe quantum beats that reflect the time evolution of the coh erence between the two lowest Landau level magnetoexcitons. We interpret our observations using a many-body theory and find that the inter Landau level coherence decays with a new time constant, substantially longer than the corresponding interband magnetoexciton dephasing times. Our results indicate a new intraband excitation dynamics that cannot be described in terms of uncorrelated interband excitations.
152 - I. G. Lang , S. T. Pavlov 2010
The light reflectance and absorbance are calculated for a quantum well (QW) the width of which is comparable with the light wave length. The difference of the refraction coefficients of the quantum well and barriers is taken into account. The stimula ting pulse form is arbitrary. An existence of two closely situated discrete excitation energy levels is supposed. Such energy level pare may correspond to two magnetopolaron states in a quantizing magnetic field perpendicular to the QW plane. The relationship of the radiative and non-radiative damping is arbitrary. The final results does not use the approximation of the weak Coulomb interaction of electrons and holes.
We report on the clear evidence of massless Dirac fermions in two-dimensional system based on III-V semiconductors. Using a gated Hall bar made on a three-layer InAs/GaSb/InAs quantum well, we restore the Landau levels fan chart by magnetotransport a nd unequivocally demonstrate a gapless state in our sample. Measurements of cyclotron resonance at different electron concentrations directly indicate a linear band crossing at the $Gamma$ point of Brillouin zone. Analysis of experimental data within analytical Dirac-like Hamiltonian allows us not only determing velocity $v_F=1.8cdot10^5$ m/s of massless Dirac fermions but also demonstrating significant non-linear dispersion at high energies.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا