Observation of a Critical Charge Mode in a Strange Metal
Abstract
Quantum electronic matter has long been understood in terms of two limiting behaviors of electrons: one of delocalized metallic states, and the other of localized magnetic states. Understanding the strange metallic behavior which develops at the brink of localization demands new probes of the underlying electronic charge dynamics. Using a state-of-the-art technique, synchrotron-radiation-based Mossbauer spectroscopy, we have studied the longitudinal charge fluctuations of the strange metal phase of beta-YbAlB4 as a function of temperature and pressure. We find that the usual single absorption peak in the Fermi-liquid regime splits into two peaks upon entering the critical regime. This spectrum is naturally interpreted as a single nuclear transition, modulated by nearby electronic valence fluctuations whose long time-scales are further enhanced, due to the formation of charged polarons. Our results represent a direct observation of critical charge fluctuations as a new signature of strange metals.
Keywords
Cite
@article{arxiv.2202.12462,
title = {Observation of a Critical Charge Mode in a Strange Metal},
author = {Hisao Kobayashi and Yui Sakaguchi and Hayato Kitagawa and Momoko Oura Shugo Ikeda and Kentaro Kuga and Shintaro Suzuki and Satoru Nakatsuji and Ryo Masuda and Yasuhiro Kobayashi and Makoto Seto and Yoshitaka Yoda and Kenji Tamasaku and Yashar Komijani and Premala Chandra and Piers Coleman},
journal= {arXiv preprint arXiv:2202.12462},
year = {2023}
}