Abstract

There has recently been increased interest in the application of squeezed light to phenomena in the spatial domain. In particular, it was shown that spatially broadband squeezed light can be used to image faint objects with subshot noise sensitivity.¹ Since an optical parametric amplifier (OPA) generates correlated photons that are spatially broadband, it is an ideal process for the initial demonstration of quantum correlations in image amplification. Quantum-noise reduction of more than 6 dB has previously been achieved by use of twin beams of light generated by a traveling-wave OPA.² Also, parametric amplification has been shown to have practical applications in timegated image recovery.^3,4 An example is the amplification of ballistic photons through turbid media for biomedical imaging.5 Here we report what we believe to be the first observation of quantum noise correlations between the spatial frequencies of a parametrically amplified image and the generated conjugate image.

© 1997 Optical Society of America