Tue October 11, 2016 4:00 pm
Creating multiparticle entanglement in an atomic ensemble with and without a cavity
Location:Jefferson-250
Dr. Jakob Reichel,
Laboratoire Kastler Brossel de l’E.N.S., France
Entanglement has grown from a quantum curiosity into a cornerstone of modern quantum theory, and acts as a resource in future technologies such as quantum metrology. I will first discuss a series of experiments where multiparticle entangled states are created in an ensemble of ~40 atoms using optical fiber microcavities and atom chips. Several different entanglement schemes are possible in this setting, including the conceptutally interesting “Quantum Zeno Dynamics” (QZD), which we have realized recently. In the second part of my talk, I will describe an experiment performed in collaboration with the French time-frequency metrology laboratory SYRTE, where spin squeezing occurs spontaneously within a standard Ramsey sequence applied to a 87Rb BEC trapped on an atom chip. A single resonant p/2 pulse is applied to all the atoms in the BEC, which is then allowed to evolve freely. The trap is cigar-shaped and trap parameters are chosen such that demixing occurs, reducing the inter-state scattering length. This scheme requires neither Feshbach resonances nor state-dependent potentials, making it attractively simple to implement.