PIRSA:16060034

How to count one photon and get a(n average) result of 1000...

APA

Steinberg, A. (2016). How to count one photon and get a(n average) result of 1000.... Perimeter Institute. https://pirsa.org/16060034

MLA

Steinberg, Aephraim. How to count one photon and get a(n average) result of 1000.... Perimeter Institute, Jun. 20, 2016, https://pirsa.org/16060034

BibTex

          @misc{ pirsa_PIRSA:16060034,
            doi = {10.48660/16060034},
            url = {https://pirsa.org/16060034},
            author = {Steinberg, Aephraim},
            keywords = {Quantum Foundations},
            language = {en},
            title = {How to count one photon and get a(n average) result of 1000...},
            publisher = {Perimeter Institute},
            year = {2016},
            month = {jun},
            note = {PIRSA:16060034 see, \url{https://pirsa.org}}
          }
          

Aephraim Steinberg University of Toronto

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.