Spectroscopy of local density of states fluctuations in a disordered conductor

Abstract
The local density of states of a degenerate semiconductor is investigated at low magnetic fields by resonant tunneling through a discrete localized energy level. Mesoscopic fluctuations of the local density of states below the Fermi level are imaged as temperature-insensitive fine structure in the tunneling current. These fluctuations are attributed to quantum interference of diffusive electron waves in the three-dimensional disordered system.