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arXiv · 0908.2485

Time-dependent currents of 1D bosons in an optical lattice

Johannes Schachenmayer·Guido Pupillo·Andrew J. Daley
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Abstract

We analyse the time-dependence of currents in a 1D Bose gas in an optical lattice. For a 1D system, the stability of currents induced by accelerating the lattice exhibits a broad crossover as a function of the magnitude of the acceleration, and the strength of the inter-particle interactions. This differs markedly from mean-field results in higher dimensions. Using the infinite Time Evolving Block Decimation algorithm, we characterise this crossover by making quantitative predictions for the time-dependent behaviour of the currents and their decay rate. We also compute the time-dependence of quasi-condensate fractions which can be measured directly in experiments. We compare our results to calculations based on phase-slip methods, finding agreement with the scaling as the particle density increases, but with significant deviations near unit filling.

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Johannes Schachenmayer, Guido Pupillo, Andrew J. Daley. 2010-03-03. Time-dependent currents of 1D bosons in an optical lattice. https://doi.org/10.1088/1367-2630%2F12%2F2%2F025014

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