Full counting statistics for noninteracting fermions: exact finite-temperature results and generalized long-time approximation.

Exact numerical results for the full counting statistics (FCS) of a one-dimensional tight-binding model of noninteracting electrons are presented at finite temperatures using an identity recently published by Abanov and Ivanov. A similar idea is used to derive an explicit expression for the cumulant generating function for a system consisting of two quasi-one-dimensional leads connected by a quantum dot in the long-time limit, generalizing the Levitov-Lesovik formula for two single-channel leads to systems with an arbitrary number of transverse channels.