Am. Kreshchuk et al., QUANTUM TRANSPORT EFFECTS IN A 2-DIMENSIONAL ELECTRON-GAS AS A TOOL FOR THE INVESTIGATION OF HETEROINTERFACES, Journal of crystal growth, 146(1-4), 1995, pp. 153-158
We have studied the influence of interface defects on low temperature
galvanomagnetic effects in a two-dimensional electron gas (2DEG). Expe
riments have shown a non-ideal character of the InP/In0.53Ga0.47As int
erface in modulation-doped structures with 2DEG grown by liquid phase
epitaxy. That is why such structures have been chosen for investigatio
n. The following galvanomagnetic effects were investigated at liquid h
elium temperatures: the Hall mobility; the oscillatory magnetoresistan
ce in a magnetic field perpendicular to the heterointerface; the negat
ive magnetoresistance in a weak magnetic field parallel to 2DEG. The q
uantitative analysis of these effects allowed one to determine the int
erface parameters: the amplitude delta = 7-10 Angstrom and the lateral
size Lambda = 50-70 Angstrom of small-scale interface fluctuation, th
e interface charge density N-z = (8 +/- 2) X 10(9) cm(-2) and the ampl
itude of large-scale 2DEG density fluctuations delta n(s)/n(s) approxi
mate to 5%.