How to count one photon and get a result of 1000 (Prof. A. Steinberg)
14:30 - 15:30
Prof. Dr. Aephraim M. Steinberg
Quantum Optics Group, Centre for Quantum Information & Quantum Control, Department of Physics, University of Toronto, Canada
New Lecture Hall, Room B 0.32
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
permitting, I will also describe other future and past work related to quantum
measurement and ultracold atoms – in particular, we have implemented a
quantum-information-inspired protocol to beat “Rayleigh’s curse” for resolving
closely-separated spots in classical imaging; and we are progressing towards an
experiment which will permit us to track where atoms spend their time while
tunneling through an optical barrier.