arXiv:2009.12554 · Journal of Physics B Atomic Molecular and Optical Physics

Quantum dark solitons in ultracold one-dimensional Bose and Fermi gases

Andrzej Syrwid

Published Dec 14, 2020• 17 citations

Abstract

Abstract Solitons are ubiquitous phenomena that appear, among others, in the description of tsunami waves, fiber-optic communication and ultracold atomic gases. The latter systems turned out to be an excellent playground for investigations of matter-wave solitons in a quantum world. This tutorial provides a general overview of the ultracold contact interacting Bose and Fermi systems in a one-dimensional space that can be described by the renowned Lieb–Liniger and Yang–Gaudin models. Both the quantum many-body systems are exactly solvable by means of the Bethe ansatz technique, granting us a possibility for investigations of quantum nature of solitonic excitations. We discuss in details a specific class of quantum many-body excited eigenstates called yrast states and show that they are strictly related to quantum dark solitons in the both considered Bose and Fermi systems.

DOI: 10.1088/1361-6455/abd37f

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