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arXiv · 1503.07606

Disappearance of Quasiparticles in a Bose Lattice Gas

David Chen·Carolyn Meldgin·Philip Russ·Erich Mueller·Brian DeMarco
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Abstract

We use a momentum-space hole-burning technique implemented via stimulated Raman transitions to measure the momentum relaxation time for a gas of bosonic atoms trapped in an optical lattice. By changing the lattice potential depth, we observe a smooth crossover between relaxation times larger and smaller than the bandwidth. The latter condition violates the Mott-Ioffe-Regal bound and indicates a breakdown of the quasi-particle picture. We produce a simple kinetic model that quantitatively predicts these relaxation times. Finally, we introduce a cooling technique based upon our hole-burning technique.

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David Chen, Carolyn Meldgin, Philip Russ, Erich Mueller, Brian DeMarco. 2015-03-26. Disappearance of Quasiparticles in a Bose Lattice Gas. https://doi.org/10.1103/physreva.94.021601

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