Photon-counting distribution in squeezed states

Abstract
We calculate the counting (multiplicity) distribution PN=〈N|ρ|N〉 where ρ is (i) the density matrix corresponding to a (pure) squeezed state and (ii) the density matrix of a superposition of squeezed states with thermal light. In the first case, we find that PN is an oscillating function of N. In the second case, this behavior, characteristic for squeezed states, disappears even for small amounts of noise.