hide
Free keywords:
-
Abstract:
The spectrum of 2D electrons subjected to a weak 2D potential and a
perpendicular magnetic field is composed of Landau bands with a fractal
internal pattern of subbands and minigaps referred to as Hofstadter's
butterfly. The Hall conductance may serve as a spectroscopic tool as
each filled subband contributes a specific quantized value. Advances in
sample fabrication now finally offer access to the regime away from the
limiting case of a very weak potential. Complex behavior of the Hall
conductance is observed and assigned to Landau band-coupling-induced
rearrangements within the butterfly.
