Reflection and absorption of QWs irradiated by light pulses in a strong   magnetic field
  It has been shown that the non-sinusoidal character oscillations appear in the transmitted, reflected and absorbed light fluxes when light pulses irradiate a semiconductor quantum well (QW), containing a set of a large number of the equidistant energy levels of electronic excitations. The oscillation amplitude is comparable to the flux values for the short pulses, duration of which \gamma_l^{-1} \leq \hbar/\Delta E. A damping echo of the exciting pulse appears through the time intervals 2\pi\hbar/\Delta E in the case of the very short light pulses \gamma_l^{-1}\ll \hbar/\Delta E. Symmetrical and asymmetrical pulses with a sharp front have been considered. Our theory is applicable for the narrow QWs in a strong magnetic field, when the equidistant energy levels correspond to the electron-hole pairs with different Landau quantum numbers. 
I.G.Lang L.I. Korovin, D.A. Contreras-Solorio and S.T.Pavlov