Postovani saradnici,

Obavestavamo Vas da ce se dana 19.06.2014. (cetvrtak), sa pocetkom u 13:00 casova,
u Biblioteci Instituta za fiziku, odrzati kolokvijum:


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"Very attractive photons"

Vladan Vuletic

Centar for Ultra-cold atoms,  Massachusetts Institute of Technology, Cambridge, US

Abstract

The fundamental properties of light derive from its constituent
particles—massless quanta (photons) that do not interact with one
another. However, it has long been known that the realization of
coherent interactions between individual photons, akin to those
associated with conventional massive particles, could enable a wide
variety of novel scientific and engineering applications. Here we
demonstrate a quantum nonlinear medium inside which individual
photons travel as massive particles with strong mutual attraction,
such that the propagation of photon pairs is dominated by a two photon
bound state. We achieve this through dispersive coupling
of light to strongly interacting atoms in highly excited Rydberg states.
We measure the dynamical evolution of the two-photon wave function
using time-resolved quantum state tomography, and demonstrate
a conditional phase shift exceeding one radian, resulting in
polarization-entangled photon pairs. Particular applications of this
technique include all-optical switching, deterministic photonic
quantum logic and the generation of strongly correlated states of
light.