Strange metallicity encompasses high magnetic field-induced superconductivity in UTe2

TL;DR

This study reveals that in UTe$_2$, strange metallicity appears in high magnetic fields where field-induced superconductivity is strongest, indicating a possible link to quantum critical fluctuations and unconventional pairing.

Contribution

It uncovers the coexistence of strange metallicity and field-induced superconductivity in UTe$_2$, highlighting a new context for quantum criticality and unconventional superconductivity.

Findings

Strange metallic behavior appears only in a narrow angular window with high magnetic fields.

Field-induced superconductivity correlates with the presence of strange metallicity.

The results suggest a shared mechanism possibly related to magnetic quantum critical fluctuations.

Abstract

The heavy fermion material UTe$_2$ hosts a suite of exotic superconducting phases, the most extreme of which resides in a narrow angular window of intense magnetic fields $>$ 40 T. Here we report that in the angular and field regime in which field-induced superconductivity is most robust, the normal-state resistivity exhibits a linear temperature dependence characteristic of strange metallicity, sharply contrasting with the Fermi-liquid behavior observed at low fields and away from this angular window. Through angle-dependent magnetotransport measurements in high magnetic fields, we find that the strange metal state is confined to a narrow angular range where field-induced superconductivity is also maximized, suggesting a shared underlying mechanism. These findings reveal a novel setting for strange metallicity - proximate to spin-triplet, field-induced superconductivity - and point to the presence of quantum critical fluctuations, likely of a magnetic origin. The coexistence of strange metallicity and putatively spin-triplet pairing challenges prevailing paradigms of non-Fermi-liquid phenomenology, and highlights UTe$_2$ as a unique platform for exploring the interplay between unconventional superconductivity and quantum criticality.