We report observation of the Hall slope change in wide Al cGa1-cAs parabolic wells in the presence of a quasi-parallel magnetic field. Above the critical magnetic field B > 4T, the Hall resistance becomes temperature dependent and can be described by equation Rxy/costheta ~ (B-B0)/en s, where n s is the electron density, B0=2-2.6 T and theta is the angle between magnetic field and the normal to the well plane. The effect strongly depends on the electron density; it is observed only in parabolic wells, which are almost completely filled by electrons. We attribute the Hall slope change to the unusual behaviour of the effective g factor in such parabolic well, which depends on the Al composition and changes the sign along the well width.

It is reported a theoretical and numerical study of non-markovian memory effects in backscattering of ballistic electrons constrained to move in a corrugated surface topography. Two approaches to model the electron trajectories are used, better approximation is obtained with the Hamilton-Dirac method for constrained system.

We compare the transport properties for triangular, parabolic and cubic quantum wells. We calculate the transport mobility for electrons belonging to the different subbands. We obtain the energy spacing between first and second subbands from the electron sheet density and compare results for different potential profiles. We find that experimental results are in quantitative agreements with our calculations.

We calculated the classical electron dynamics of three-dimensional electrons in a billiard system in tilted magnetic field and analyzed the evolution of trajectories in phase space by means of Poincaré space of sections. The low field magnetoresistance rhoxx was calculated through linear response theory and found that nonlinear resonances between the cyclotron radius Rc, the antidot lattice period a, and the well width W, are reflected in the observed magnetoresistance peaks.