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arXiv · 1309.1552

Experimental realization of quantum zeno dynamics

Florian Schäfer·Ivan Herrera·Shahid Cherukattil·Cosimo Lovecchio·Francesco Saverio Cataliotti·Filippo Caruso·Augusto Smerzi
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Abstract

It is generally impossible to probe a quantum system without disturbing it. However, it is possible to exploit the back-action of quantum measurements and strong couplings to tailor and protect the coherent evolution of a quantum system. This is a profound and counterintuitive phenomenon known as quantum Zeno dynamics (QZD). Here we demonstrate QZD with a rubidium Bose-Einstein condensate in a five-level Hilbert space. We harness measurements and strong couplings to dynamically disconnect different groups of quantum states and constrain the atoms to coherently evolve inside a two-level subregion. In parallel to the foundational importance due to the realization of a dynamical superselection rule and the theory of quantum measurements, this is an important step forward in protecting and controlling quantum dynamics and, broadly speaking, quantum information processing.

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Florian Schäfer, Ivan Herrera, Shahid Cherukattil, Cosimo Lovecchio, Francesco Saverio Cataliotti, Filippo Caruso, Augusto Smerzi. 2014-02-02. Experimental realization of quantum zeno dynamics. https://doi.org/10.1038/ncomms4194

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