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arXiv · 2409.19475

Higgs-like stiffness and fractons on the verge of phase transitions

Lucas Squillante·Antonio C. Seridonio·Roberto E. Lagos-Monaco·Mariano de Souza
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Abstract

In condensed matter Physics, massive longitudinal Higgs modes emerge from fluctuations of the order parameter. A few years ago, the Higgs mode was \emph{caught} experimentally in the vicinity of an insulator-to-superconductor quantum phase transition [Nat. Phys. $\textbf{11}$, 188 (2015)]. Here, we propose, in analogy to the Higgs mode, the concept of Higgs-like stiffness (HLS), which emerges close to both classical and quantum phase transitions as a universal manifestation of matter. We build up a Landau free energy for the dielectric response function to demonstrate that \emph{any} complex physical quantity can be used to infer the presence of the HLS. Our analysis is corroborated by experimental results of the quasi-static dielectric constant for the (TMTTF)$_2$SbF$_6$ Fabre salt. Yet, we discuss the appearance of fractons in connection with the locking of particular molecular rotational degrees of freedom.

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Lucas Squillante, Antonio C. Seridonio, Roberto E. Lagos-Monaco, Mariano de Souza. 2024-09-28. Higgs-like stiffness and fractons on the verge of phase transitions. https://arxiv.org/abs/2409.19475

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