Avouris and co-workers have shown that oscillations from steps on Au(111) oscillate as cos(2kF x), where x is the distance from the step, that agrees with theoretical eq. 15. Their theoretical findings show that such decay and kF should be characteristic to any 2D electron gas surface. On the other hand, they have shown that higher temperature can increase the oscillation period due to the Fermi distribution of the STM tip and sample, as denoted by their (dI/dV)/(I/V) scans that correspond to 1/r 2 decay rate.