Spin-orbit interaction in AlAs quantum wells

The spin-orbit coupling was investigated in a series of AlAs quantum wells with different width containing high quality two dimensional electron systems. The interaction between the spin degree of freedom and the orbital motion of the electrons in the regime of the integer quantum Hall effect induced the filling factor dependent renormalization of the electron g-factor. Such g-factor modification probed by electron spin resonance was well resolved in all of the samples studied in a wide range of magnetic fields. Theoretical analysis of this phenomenon allowed us to identify the Dresselhaus-like spin-orbit interaction as the dominant term and to measure its strength β. The value of β turned out to depend rather weakly on the quantum well width, yet such a behavior agrees well with the theoretical calculations. The bulk Dresselhaus constant extracted from the fit turned out to be 3.5 eV × Å3.