@ARTICLE{ISI:000176907500031,
  author = {Cserti, J and Kormányos, A and Kaufmann, Z and Koltai, J and Lambert,
	C J},
  title = {Proximity-induced subgaps in Andreev billiards},
  journal = {Physical Review Letters},
  year = {2002},
  volume = {89},
  pages = {057001},
  number = {5},
  abstract = {We examine the density of states of an Andreev billiard and show that
	any billiard with a finite upper cutoff in the path length distribution
	P(s) will possess an energy gap on the scale of the Thouless energy.
	An exact quantum mechanical calculation for different Andreev billiards
	gives good agreement with the semiclassical predictions when the
	energy dependent phase shift for Andreev reflections is properly
	taken into account. Based on this new semiclassical Bohr-Sommerfeld
	approximation of the density of states, we derive a simple formula
	for the energy gap. We show that the energy gap, in units of Thouless
	energy, may exceed the value predicted earlier from random matrix
	theory for chaotic billiards.},
  doi = {10.1103/PhysRevLett.89.057001},
  issn = {0031-9007},
  keywords = {Transport ; Andreev reflection ; semiclassical},
  mount = {JUL 29},
  unique-id = {ISI:000176907500031},
  url = {http://prola.aps.org/pdf/PRL/v89/i5/e057001}
}