Non-Fermi-Liquid Behaviors in Weakly Interacting Two-Dimensional Quasicrystals

Junmo Jeon; Shiro Sakai

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arXiv · 2607.18394

Non-Fermi-Liquid Behaviors in Weakly Interacting Two-Dimensional Quasicrystals

Junmo Jeon·Shiro Sakai

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Abstract

Non-Fermi-liquid (NFL) behavior is usually associated with strong electronic correlations, quantum criticality, or singular fluctuations that invalidate the quasiparticle picture. Quasicrystals are known to provide a fundamentally different route to such physics: their lack of translational symmetry gives rise to critical single-particle states and fragmented spectra even in the absence of electron-electron interactions. Here, we numerically study the NFL behaviors in quasicrystals with weak interactions. Using Penrose and Ammann--Beenker tilings as representative quasiperiodic systems, we analyze thermodynamic, magnetic, and transport properties within a weak-coupling perturbative framework. The Sommerfeld coefficient and magnetic susceptibility show anomalous temperature dependences governed by the singular energy dependence of the density of states near the Fermi level. The Wilson ratio reveals that low-temperature NFL behavior in quasicrystals is accompanied by enhanced spin fluctuations over a broad range of filling fractions, while its magnitude and temperature dependence vary sensitively with filling fraction. The self-energy shows anomalous scaling and a finite residual scattering rate, indicating the breakdown of quasiparticles. Our site-resolved analysis reveals a pronounced enhancement of the residual scattering rate in regions with a high local density of states. These results serve as a guide to analyze experimental data for quasicrystals and to identify the microscopic mechanism of the NFL behaviors.

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Junmo Jeon, Shiro Sakai. 2026-07-20. Non-Fermi-Liquid Behaviors in Weakly Interacting Two-Dimensional Quasicrystals. https://arxiv.org/abs/2607.18394

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