International Journal of Modern Physics B

NON-DEMOLITIVE PHOTON NUMBER MEASUREMENT VIA χ(2) NONLINEARITY

Stefania Castelletto, Ivo Pietro Degiovanni, Maria Luisa Rastello

Published Nov 10, 1999• 1 citation

Abstract

The aim of this paper is to present a possible experiment for measuring photon number by a non-demolitive scheme. We show that, in principle, it is possible to deduce the number of photons of an intense pump coherent field by measuring the phase-shift on two frequency conjugated beams due to the interaction with the pump in a nonlinear crystal, which exhibits χ(2) nonlinearity. We perform a theoretical evaluation of the relative uncertainty associated to the photon number measurement, obtaining high accuracy results when high pump power levels, low coupling between pump and crystal and squeezing generators are used. The accuracy obtained are compared with results obtainable with a beam splitter setup.

DOI: 10.1142/s0217979299003088

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