title: Surmounting intrinsic quantum-measurement uncertainties in Gaussian-state tomography with quadrature squeezing.
abstract: We reveal that quadrature squeezing can result in significantly better quantum-estimation performance with quantum heterodyne detection (of H. P. Yuen and J. H. Shapiro) as compared to quantum homodyne detection for Gaussian states, which touches an important aspect in the foundational understanding of these two schemes. Taking single-mode Gaussian states as examples, we show analytically that the competition between the errors incurred during tomogram processing in homodyne detection and the Arthurs-Kelly uncertainties arising from simultaneous incompatible quadrature measurements in heterodyne detection can often lead to the latter giving more accurate estimates. This observation is also partly a manifestation of a fundamental relationship between the respective data uncertainties for the two schemes. In this sense, quadrature squeezing can be used to overcome intrinsic quantum-measurement uncertainties in heterodyne detection.
authors.affiliation: Department of Optics, Palacký University, 17. listopadu 12, 77146 Olomouc, Czech Republic.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Řeháček
authors.affiliation: Department of Optics, Palacký University, 17. listopadu 12, 77146 Olomouc, Czech Republic.
authors.forename: Yong Siah
authors.initials: YS
authors.lastname: Teo
authors.affiliation: Department of Optics, Palacký University, 17. listopadu 12, 77146 Olomouc, Czech Republic.
authors.forename: Zdeněk
authors.initials: Z
authors.lastname: Hradil
authors.affiliation: Instituto de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22, Chile.
authors.forename: Sascha
authors.initials: S
authors.lastname: Wallentowitz