Thouless energy

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

The Thouless energy is a characteristic energy scale of diffusive disordered conductors. It was first introduced by the Scottish-American physicist David J. Thouless when studying Anderson localization,[1] as a measure of the sensitivity of energy levels to a change in the boundary conditions of the system. Though being a classical quantity, it has been shown to play an important role in the quantum-mechanical treatment of disordered systems.[2]

It is defined by


where D is the diffusion constant and L the size of the system, and thereby inversely proportional to the diffusion time

through the system.


  1. ^ J. T. Edwards and D. J. Thouless, "Numerical studies of localization in disordered systems," J. Phys. C: Solid State Phys. 5, 807 (1972), [1] doi:10.1088/0022-3719/5/8/007.
  2. ^ A. Altland, Y. Gefen, and G. Montambaux, "What is the Thouless Energy for Ballistic Systems?", Physical Review Letters 76, 1130 (1996), [2] doi:10.1103/PhysRevLett.76.1130.