Ov. Volkov et al., MAGNETOPLASMON REPLICA IN THE RECOMBINATION RADIATION SPECTRA OF A QUASI-2-DIMENSIONAL ELECTRON-GAS IN GAAS ALGAAS QUANTUM-WELLS/, JETP letters, 66(8), 1997, pp. 575-580
The radiative recombination spectra of two-dimensional electrons with
free photoexcited holes are investigated for a wide variety of GaAs/Al
GaAs quantum wells, with different thicknesses and electron densities.
It is found that for certain, close to integral, filling factors an i
ntense line corresponding to an Auger process - radiative recombinatio
n with the emission of an additional magnetoplasmon - appears in the l
uminescence spectrum. The new line is shifted to lower energies with r
espect to the zero Landau level, and the magnetic field dependence of
the energy splitting between these lines agrees with the theoretical c
oncepts of the dispersion of magnetoplasmon excitations. This makes it
possible to estimate the magnetoplasmon energy at the roton minimum.
(C) 1997 American Institute of Physics.