Clausen, J.J.ClausenDakna, M.M.DaknaKnoll, L.L.KnollWelsch, D. G.D. G.Welsch2018-11-072018-11-072000https://resolver.sub.uni-goettingen.de/purl?gro-2/48692We propose a detection scheme for measuring the overlap of the quantum state of a traveling-field mode with a reference quantum state that is an arbitrary superposition of a finite land under realistic conditions small) number N of Fock states, \Psi]= Sigma(n)(N)=(0)c(n)\ n]. In the scheme, an array of maximally N beam splitters is used in which the signal mode is successively mixed with modes prepared in coherent states and photon-number measurements are performed. To illustrate the method, we discuss the measurement of the quantum phase and the detection of Schrodinger-cat-like states. (C) 2000 Elsevier Science B.V. All rights reserved.Measuring quantum state overlaps of traveling optical fieldsjournal_article10.1016/S0030-4018(99)00537-4000087741900023