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arXiv · 1603.09507

Dynamics of fermions in an amplitude modulated lattice

Tomotake Yamakoshi·Shinichi Watanabe·Shun Ohgoda·Alexander P. Itin
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Abstract

We study dynamics of fermions loaded in an optical lattice with a superimposed parabolic trap potential. In the recent Hamburg experiments [J.Heinze et.al., Phys. Rev. Lett. 110, 085302 (2013)] on quantum simulation of photoconductivity, a modulation pulse on the optical lattice transferred part of the population of the lowest band to an excited band, leaving a hole in the particle distribution of the lowest band. Subsequent intricate dynamics of both excited particles and holes can be explained by a semiclassical approach based on the evolution of Wigner function. Here we provide a more detailed analysis of the dynamics taking into account the dimensionality of the system and finite temperature effects, aiming at reproducing experimental results on longer timescales. A semiclassical wave packet is constructed more accurately than in the previous theory. As a result, semiclassical dynamics indeed reproduces experimental data and full quantum numerical calculations with much better accuracy. In particular, fascinating phenomenon of collapse and revival of holes is investigated in a more detail. We presume the experimental setup can be used for deeper exploration of nonlinear waves in fermionic gases.

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Tomotake Yamakoshi, Shinichi Watanabe, Shun Ohgoda, Alexander P. Itin. 2016-03-31. Dynamics of fermions in an amplitude modulated lattice. https://doi.org/10.1103/physreva.93.063637

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