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A five-level {Pp} model of the band structure for GaAs-type semiconductors is used to describe the spin $g^*$-factor and the cyclotron mass $m^*_c$ of conduction electrons in GaAs/Ga$_{1-x}$Al$_x$As quantum wells in an external magnetic field parallel to the growth direction. It is demonstrated that the previous theory of the $g^*$-factor in heterostructures is inadequate. Our approach is based on an iteration procedure of solving 14 coupled differential {Pp} equations. The applicability of the iteration procedure is verified. The final eigenenergy problem for the conduction subbands is reduced to two differential equations for the spin-up and spin-down states of consecutive Landau levels. It is shown that the bulk inversion asymmetry of III-V compounds is of importance for the spin $g^*$-factor. Our theory with no adjustable parameters gives an excellent description of experimental data on the electron spin $g^*$-factor in GaAs/Ga$_{0.67}$Al$_{0.33}$As rectangular quantum wells for different well widths between 3 and 12 nm. The same theory describes very well experimental cyclotron masses in GaAs/Ga$_{0.74}$Al$_{0.26}$As quantum wells for the well widths between 6 and 37 nm.
In a recent publication, Pfeffer and Zawadzki [cond-mat/0607150; Phys. Rev. B 74, 115309 (2006)] attempted a calculation of electron g factor in III-V heterostructures. The authors emphasize that their outcome is in strong discrepancy with our origin
We report on transport signatures of hidden quantum Hall stripe (hQHS) phases in high ($N > 2$) half-filled Landau levels of Al$_{x}$Ga$_{1-x}$As/Al$_{0.24}$Ga$_{0.76}$As quantum wells with varying Al mole fraction $x < 10^{-3}$. Residing between the
We report on transport signatures of eight distinct bubble phases in the $N=3$ Landau level of a Al$_{x}$Ga$_{1-x}$As/Al$_{0.24}$Ga$_{0.76}$As quantum well with $x = 0.0015$. These phases occur near partial filling factors $ u^star approx 0.2,(0.8)$
We have measured the magnetoresistance in a series of Ga$_{1-x}$Mn$_x$As samples with 0.033$le x le$ 0.053 for three mutually orthogonal orientations of the applied magnetic field. The spontaneous resistivity anisotropy (SRA) in these materials is ne
The electron-electron interaction quantum correction to the conductivity of the gated double well Al$_x$Ga$_{1-x}$As/GaAs structures is investigated experimentally. The analysis of the temperature and magnetic field dependences of the conductivity te