Picture of a sphere with binary code

Making Strathclyde research discoverable to the world...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs. It exposes Strathclyde's world leading Open Access research to many of the world's leading resource discovery tools, and from there onto the screens of researchers around the world.

Explore Strathclyde Open Access research content

Retrodiction for optical attenuators, amplifiers, and detectors

Jedrkiewicz, Ottavia and Loudon, Rodney and Jeffers, John (2004) Retrodiction for optical attenuators, amplifiers, and detectors. Physical Review A, 70 (3). 033805-1. ISSN 1094-1622

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

The transformation that an attenuator makes on the state of an optical field is the time reverse of that of an amplifier. Thus predicting the output state for an amplifier is equivalent to retrodicting the input state of an attenuator. We explore the consequences of this equivalence for simple optical quantum communication channels. One counterintuitive consequence is that the mean number of photons sent into an amplifier as retrodicted from a measurement of the number of output photons does not include the contribution of the amplifier noise.