A fundamental challenge to our current understanding of metals is the frequent observation of qualitative departures from Fermi liquid behavior. The standard view attributes such non-Fermi liquid phenomena to the scattering of electrons off quantum critical fluctuations of an underlying order parameter. While the possibility of non-Fermi liquid behavior isolated from the border of magnetism has long been speculated, no experimental confirmation has been made. Here we report on the observation of a strange metal region in the absence of a magnetic instability in an ultrapure single crystal. In particular, we show that the heavy fermion superconductor β-YbAlB4 forms a possible phase with strange metallic behavior across an extensive pressure regime, distinctly separated from a high-pressure magnetic quantum phase transition by a Fermi liquid phase.
@article{arxiv.1508.02536,
title = {Strange metal without magnetic criticality},
author = {Takahiro Tomita and Kentaro Kuga and Yoshiya Uwatoko and Piers Coleman and Satoru Nakatsuji},
journal= {arXiv preprint arXiv:1508.02536},
year = {2015}
}