Effect of dephasing on charge-counting statistics in chaotic cavities

We calculate the cumulants of the charge transmitted through a chaotic cavi ty in the limit that the two openings have a large number of scattering cha nnels. The shot noise, which is the second cumulant, is known to be insensi tive to dephasing in this limit. Unexpectedly, the fourth and higher cumula nts are found to depend on dephasing: A semiclassical theory and a quantum mechanical model with strong dephasing give a result different from a fully phase-coherent quantum mechanical theory. (C) 2001 Elsevier Science B.V. A ll rights reserved.