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Loschmidt echo in the Bose-Hubbard model: turning back time in an optical lattice

Fernando M. Cucchietti
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Abstract

I show how to perform a Loschmidt echo (time reversal) in the Bose-Hubbard model implemented with cold bosonic atoms in an optical lattice. The echo is obtained by applying a linear phase imprint on the lattice and a change in magnetic field to tune the boson-boson scattering length through a Feshbach resonance. I discuss how the echo can measure the fidelity of the quantum simulation, the intensity of an external potential (e.g. gravity), or the critical point of the superfluid-insulator quantum phase transition.

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Fernando M. Cucchietti. 2006-09-26. Loschmidt echo in the Bose-Hubbard model: turning back time in an optical lattice. https://doi.org/10.1364/josab.27.000a30

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