title: HEAVY FERMIONS. Strange metal without magnetic criticality.
abstract: A fundamental challenge to our current understanding of metals is the 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. Although 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 away from 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.
authors.affiliation: Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan. College of Humanities and Sciences, Nihon University, Setagaya 156-8550, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tomita
authors.affiliation: Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kuga
authors.affiliation: Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan.
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Uwatoko
authors.affiliation: Center for Materials Theory, Department of Physics and Astronomy, Rutgers University, Piscataway, N.J. 08854, USA. Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK.
authors.forename: Piers
authors.initials: P
authors.lastname: Coleman
authors.affiliation: Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan. PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan. satoru@issp.u-tokyo.ac.jp.
authors.forename: Satoru
authors.initials: S
authors.lastname: Nakatsuji