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arXiv · 1904.04313

Information geometric analysis of long range topological superconductors

Abstract

The Uhlmann connection is a mixed state generalisation of the Berry connection. The latter has a very important role in the study of topological phases at zero temperature. Closely related, the quantum fidelity is an information theoretical quantity which is a measure of distinguishability of quantum states. Moreover, it has been extensively used in the analysis of quantum phase transitions. In this work, we study topological phase transitions in 1D and 2D topological superconductors with long-range hopping and pairing amplitudes, using the fidelity and the quantity $\Delta$ closely related to the Uhlmann connection. The drop in the fidelity and the departure of $\Delta$ from zero signal the topological phase transitions in the models considered. The analysis of the ground state fidelity susceptibility and its associated critical exponents are also applied to the study of the aforementioned topological phase transitions.

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Syed Tahir Amin, Bruno Mera, Nikola Paunković, Vítor R. Vieira. 2019-04-08. Information geometric analysis of long range topological superconductors. https://doi.org/10.1088/1361-648x/ab3c70

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