PROBING THE INTERFACE FLUCTUATIONS IN SEMICONDUCTOR SUPERLATTICES USING A MAGNETOTRANSPORT TECHNIQUE

We have analysed the vertical transport properties of a GaAs/AlAs shor t period superlattice as the crossed magnetic field is rotated in the plane of the layers. The rotation of the magnetic field has been used to probe the interface roughness along the different in-plane crystall ographic directions. Two maxima separated by 180-degrees in the curren t intensity have been observed when the magnetic field is rotated thro ugh 360-degrees. We interpret our results in terms of anisotropic scat tering from elliptical interface defects of which the great axis is al ong [11OBAR0] and the minor one along [110].