Non-Fermi-liquid behavior in nearly ferromagnetic metallic SrIrO3 single crystals

TL;DR

This study reveals that SrIrO3 exhibits non-Fermi-liquid behavior near a ferromagnetic quantum critical point, characterized by anomalous magnetic, thermodynamic, and transport properties in single crystals.

Contribution

It provides detailed experimental evidence of non-Fermi-liquid behavior in SrIrO3 near a ferromagnetic instability, highlighting its quantum critical properties.

Findings

Enhanced magnetic susceptibility diverges at low T

Heat capacity shows -Tlog T dependence

Electrical resistivity follows T^{3/2} dependence

Abstract

We report transport and thermodynamic properties of single-crystal SrIrO3 as a function of temperature T and applied magnetic field H. We find that SrIrO3 is a non-Fermi-liquid metal near a ferromagnetic instability, as characterized by the following properties: (1) small ordered moment but no evidence for long-range order down to 1.7 K; (2) strongly enhanced magnetic susceptibility that diverges as T or T1/2 at low temperatures, depending on the applied field; (3) heat capacity C(T,H) ~ -Tlog T that is readily amplified by low applied fields; (4) a strikingly large Wilson ratio at T< 4K; and (5) a T3/2-dependence of electrical resistivity over the range 1.7 < T < 120 K. A phase diagram based on the data implies SrIrO3 is a rare example of a stoichiometric oxide compound that exhibits non-Fermi-liquid behavior near a quantum critical point (T = 0 and H = 0.23 T).