Tomography and state reconstruction with superconducting single-photon   detectors
  We perform quantum state reconstruction of coherent and thermal states with a detector which has an enhanced multiphoton response. The detector is based on superconducting nanowires, where the bias current sets the dependence of the click probability on the photon number; this bias current is used as tuning parameter in the state reconstruction. The nonlinear response makes our nanowire-based detector superior to the linear detectors that are conventionally used for quantum state reconstruction. 
Jelmer J. Renema, Giulia Frucci, Michiel J. A. de Dood, Richard Gill,   Andrea Fiore, Martin P. van Exter
quant-ph cond-mat.supr-con