@Article{Prevedel_etal2011,
author="Prevedel, Robert
and Hamel, Deny R.
and Colbeck, Roger
and Fisher, Kent
and Resch, Kevin J.",
title="Experimental investigation of the uncertainty principle in the presence of quantum memory and its application to witnessing entanglement",
journal="Nature Physics",
year="2011",
volume="7",
number="10",
pages="757--761",
optkeywords="fromIPMRAS",
abstract="Heisenberg{\textquoteright}s uncertainty principle provides a fundamental limitation on the ability of an observer holding classical information to predict the outcome when one of two measurements is performed on a quantum system. However, an observer with access to a particle (stored in a quantum memory) which is entangled with the system generally has a reduced uncertainty: indeed, if the particle and system are maximally entangled, the observer can perfectly predict the outcome of whichever measurement is chosen. This effect has recently been quantified in a new entropic uncertainty relation. Here we experimentally investigate this relation, showing its effectiveness as an efficient entanglement witness. We use entangled photon pairs, an optical delay line serving as a simple quantum memory and fast, active feed-forward. Our results quantitatively agree with the new uncertainty relation. Our technique acts as a witness for almost all entangled states in our experiment as we obtain lower uncertainties than would be possible without the entangled particle.",
optnote="exported from refbase (https://db.rplab.ru/refbase/show.php?record=821), last updated on Sat, 12 May 2012 14:56:44 -0500"
}