Universal Thermodynamic Signature of Self-dual Quantum Critical Points

Long Zhang

doi:10.1103/physrevlett.123.230601

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arXiv · 1903.09217

Universal Thermodynamic Signature of Self-dual Quantum Critical Points

Long Zhang

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Abstract

Self-duality is an algebraic structure of certain critical theories, which is not encoded in the scaling dimensions and critical exponents. In this work, a universal thermodynamic signature of self-dual quantum critical points (QCPs) is proposed. It is shown that the Grüneisen ratio at a self-dual QCP remains finite as $T\rightarrow 0$, which is in sharp contrast to its universal divergence at a generic QCP without self-duality, $Γ(T,g_{c})\sim T^{-1/zν}$. This conclusion is drawn based on the hyperscaling theory near the QCP, and has far-reaching implications for experiments and numerical simulations.

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Long Zhang. 2019-12-04. Universal Thermodynamic Signature of Self-dual Quantum Critical Points. https://doi.org/10.1103/physrevlett.123.230601

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