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arXiv · 2306.05845

Heat transport in a Coulomb ion crystal with a topological defect

Abstract

The thermodynamics of low-dimensional systems departs significantly from phenomenologically deducted macroscopic laws. Particular examples, not yet fully understood, are provided by the breakdown of Fourier's law and the ballistic transport of heat. Low-dimensional trapped ion systems provide an experimentally accessible and well-controlled platform for the study of these problems. In our work, we study the transport of thermal energy in low-dimensional trapped ion crystals, focusing in particular on the influence of the Aubry-like transition that occurs when a topological defect is present in the crystal. We show that the transition significantly hinders efficient heat transport, being responsible for the rise of a marked temperature gradient in the non-equilibrium steady state. Further analysis reveals the importance of the motional eigenfrequencies of the crystal.

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L. Timm, H. Weimer, L. Santos, T. E. Mehlstäubler. 2023-06-09. Heat transport in a Coulomb ion crystal with a topological defect. https://doi.org/10.1103/physrevb.108.134302

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