title: Precision quantum metrology and nonclassicality in linear and nonlinear detection schemes.
abstract: We examine whether metrological resolution beyond coherent states is a nonclassical effect. We show that this is true for linear detection schemes but false for nonlinear schemes, and propose a very simple experimental setup to test it. We find a nonclassicality criterion derived from quantum Fisher information.
authors.affiliation: Institut für Theoretische Physik, Universität Ulm, Ulm D-89069, Germany.
authors.forename: Angel
authors.initials: A
authors.lastname: Rivas
authors.forename: Alfredo
authors.initials: A
authors.lastname: Luis