Impurity and soliton dynamics in a Fermi gas with nearest-neighbor interactions

A. -M. Visuri; P. Törmä; T. Giamarchi

doi:10.1103/physreva.95.063605

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arXiv · 1701.01845

Impurity and soliton dynamics in a Fermi gas with nearest-neighbor interactions

A. -M. Visuri·P. Törmä·T. Giamarchi

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Abstract

We study spinless fermions with repulsive nearest-neighbor interactions perturbed by an impurity particle or a local potential quench. Using the numerical time-evolving block decimation method and a simplified analytic model, we show that the pertubations create a soliton-antisoliton pair. If solitons are already present in the bath, the two excitations have a drastically different dynamics: The antisoliton does not annihilate with the solitons and is therefore confined close to its origin while the soliton excitation propagates. We discuss the consequences for experiments with ultracold gases.

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BibTeX RIS

A. -M. Visuri, P. Törmä, T. Giamarchi. 2017-08-02. Impurity and soliton dynamics in a Fermi gas with nearest-neighbor interactions. https://doi.org/10.1103/physreva.95.063605

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