Statistics of charge transport and unconventional time ordering

摘要

The statistics of charge transport across a tunnel junction withenergy-dependent scattering is investigated. A model with quadratic dispersionrelation is discussed in general and, independently, in the two limiting casesof a large detector and of a linear dispersion relation. The measurement ofcharge takes place according to various protocols. It is found that, as a rule,the statistics is expressed by means of time-ordered current correlators,differing however from the conventional ones in the ordering prescription.Nevertheless binomial statistics is confirmed in all cases.