Counting statistics of photons produced by electronic shot noise

A theory is presented for the photodetection statistics of radiation produc ed by current fluctuations in a phase-coherent conductor. Deviations are fo und from the Poisson statistics that would result from a classical current. For detection in a narrow frequency interval. delta omega, the photocount distribution has the negative-binomial form of blackbody radiation if e del ta omega is less than the mean current (I) over bar in the conductor. When electronic localization sets in, (I) over bar drops below e delta omega, an d a different type of super-Poissonian photon statistics results. DOI: 10.1 103/PhysReVLett.86.700.