The magnetoresistance of the MBE-grown GaAs/AlGaAs superlattice with Si-doped barriers has been measured in tilted magnetic fields in the as-grown state, and after brief illumination by a red-light diode at low temperature, T is approximately 0.3 K. A remarkable illumination-induced modification of magnetoresistance curves has been observed, which indicates a significant change of the superlattice Fermi surface topology. Analysis of magnetoresistance data in terms of the tight-binding model reveals that not only electron concentration and mobility have been increased by illumination, but also the coupling among 2D electron layers in neighboring quantum wells has been reduced.
@article{arxiv.0705.4615,
title = {Illumination-induced changes of the Fermi surface topology in three-dimensional superlattices},
author = {N. A. Goncharuk and L. Smrcka and P. Svoboda and P. Vasek and J. Kucera and Yu. Krupko and W. Wegscheider},
journal= {arXiv preprint arXiv:0705.4615},
year = {2007}
}
Comments
7 pages, 6 figures, accepted for publication in Phys. Rev. B