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arXiv · 2007.07273

Detecting Topological Quantum Phase Transitions via the c-Function

Matteo Baggioli·Dimitrios Giataganas
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Abstract

We propose the c-function as a new and accurate probe to detect the location of topological quantum critical points. As a direct application, we consider a holographic model which exhibits a topological quantum phase transition between a topologically trivial insulating phase and a gapless Weyl semimetal. The quantum critical point displays a strong Lifshitz-like anisotropy in the spatial directions and the quantum phase transition does not follow the standard Landau paradigm. The c-function robustly shows a global feature at the quantum criticality and distinguishes with great accuracy the two separate zero temperature phases. Taking into account the relation of the c-function with the entanglement entropy, we conjecture that our proposal is a general feature of quantum phase transitions and that is applicable beyond the holographic framework.

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Matteo Baggioli, Dimitrios Giataganas. 2020-07-14. Detecting Topological Quantum Phase Transitions via the c-Function. https://doi.org/10.1103/physrevd.103.026009

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