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PERIMETER INSTITUTE RECORDED SEMINAR ARCHIVE

PIRSA:16060034  ( MP4 Medium Res , MP3 , PDF ) Which Format?
How to count one photon and get a(n average) result of 1000...
Speaker(s): Aephraim Steinberg
Abstract: I will present our recent experimental work using electromagnetically induced transparency in laser-cooled atoms to measure the nonlinear phase shift created by a single post-selected photon, and its enhancement through "weak-value amplification." Put simply, due to the striking effects of "post-selective" quantum measurements, a (very uncertain) measurement of photon number can yield an average value much larger than one, even when it is carried out on a single photon. I will say a few words about possible practical applications of this "weak value amplification" scheme, and their limitations. Time permitting, I will also describe other future and past work using "weak measurement," such as our studies quantifying the disturbance due to a measurement and what happens when it destroys interference; and our project to measure "where a particle has been" as it tunnels through a classically forbidden region – our prediction being that it will make it from one side of the barrier to the other without spending any significant time in the middle.
Date: 20/06/2016 - 10:00 am
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