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arXiv · 1804.03726

Necessary and sufficient condition for quantum adiabaticity in a driven one-dimensional impurity-fluid system

Abstract

We study under what conditions the quantum adiabaticity is maintained in a closed many-body system consisting of a one-dimensional fluid and an impurity particle dragged through the latter by an external force. We employ an effective theory describing the low-energy sector of the system to derive the time dependence of the adiabaticity figure of merit -- the adiabatic fidelity. We find that in order to maintain adiabaticity in a large system the external force, $F_N$, should vanish with the system size, $N$, as $1/N$ or faster. This improves the necessary adiabatic condition $F_N=O(1/\log N)$ obtained for this system earlier [AIP Conf. Proc. 1936, 020024 (2018)]. Experimental implications of this result and its relation to the quasi-Bloch oscillations of the impurity are discussed.

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Oleg Lychkovskiy, Oleksandr Gamayun, Vadim Cheianov. 2018-07-06. Necessary and sufficient condition for quantum adiabaticity in a driven one-dimensional impurity-fluid system. https://doi.org/10.1103/physrevb.98.024307

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