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Optics Letters

Magneto-optical spectroscopy with entangled photons

G. S. Agarwal, Marlan O. Scully

Published Mar 15, 2003• 22 citations
Publisher

Abstract

We suggest a way in which entangled photons produced by a type II downconverter can be used for magneto-optical spectroscopy with district advantages. Both collinear and noncollinear geometries can be used. We present quantum mechanical results for the coincidence detection of different polarizations at the output.
DOI
10.1364/ol.28.000462

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Recent theoretical and experimental papers have shown how one can achieve Heisenberg-limited measurements by using entangled photons. Here we show how the photons in a noncollinear down-conversion process can be used for improving the sensitivity of magneto-optical rotation by a factor of 4 which takes us towards the Heisenberg limit. Our results apply to sources with arbitrary pumping. We also present several generalizations of earlier results for the collinear geometry. The sensitivity depends on whether the two-photon or four-photon coincidence detection is used.
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