Evading Vacuum Noise: Wigner Projections or Husimi Samples?
  The accuracy in determining the quantum state of a system depends on the type of measurement performed. Homodyne and heterodyne detection are the two main schemes in continuous-variable quantum information. The former leads to a direct reconstruction of the Wigner function of the state, whereas the latter samples its Husimi $Q$~function. We experimentally demonstrate that heterodyne detection outperforms homodyne detection for almost all Gaussian states, the details of which depend on the squeezing strength and thermal noise. 
Christian R. M\"uller, Christian Peuntinger, Thomas Dirmeier, Imran   Khan, Ulrich Vogl, Christoph Marquardt, Gerd Leuchs, L...
quant-ph