Müller, C. R.Peuntinger, P.Dirmeier, ThomasKhan, I.Vogl, U.Leuchs, GerdSánchez Soto, Luis LorenzoTeo, Y. S.Hradil, ZdenekŘeháček, J.2023-06-172023-06-172016-08-110031-900710.1103/PhysRevLett.117.070801https://hdl.handle.net/20.500.14352/19001© 2016 American Physical Society. We thank Herbert Welling and Sascha Wallentowitz for discussions about different aspects of optical heterodyne detection. We acknowledge financial support from the European Research Council (Advanced Grant PACART), the Spanish MINECO (Grant No. FIS2015-67963-P), the Technology Agency of the Czech Republic (Grant No. TE01020229), the Grant Agency of the Czech Republic (Grant No. 15-03194S), and the IGA Project of Palacký University (Grant No. IGA PrF 2016-005).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.engjournal articlehttp://dx.doi.org/10.1103/PhysRevLett.117.070801http://journals.aps.org/open access535Quantum key distributionHeterodyne-detectionHomodyne detectionOptical homodyneState tomographyExcess-noisePhaseInformationUncertaintiesVariablesÓptica (Física)2209.19 Óptica Física