Magnetotransport of dirty-limit van Hove singularity quasiparticles

Yang Xu,Simon Gerber,Johan Chang,Lakshmi Das,Mark H Fischer,Jonathan Spring,Andreas Schilling,Rosalba Fittipaldi,Daniel Destraz,Jakub Vonka,Marta Gibert,František Herman,Shiyan Li,Veronica Granata,Xiaofu Zhang,Antonio Vecchione

doi:10.1038/s42005-020-00504-0

Abstract

Tuning of electronic density-of-states singularities is a common route to unconventional metal physics. Conceptually, van Hove singularities are realized only in clean two-dimensional systems. Little attention has therefore been given to the disordered (dirty) limit. Here, we provide a magnetotransport study of the dirty metamagnetic system calcium-doped strontium ruthenate. Fermi liquid properties persist across the metamagnetic transition, but with an unusually strong variation of the Kadowaki-Woods ratio. This is revealed by a strong decoupling of inelastic electron scattering and electronic mass inferred from density-of-state probes. We discuss this Fermi liquid behavior in terms of a magnetic field tunable van Hove singularity in the presence of disorder. More generally, we show how dimensionality and disorder control the fate of transport properties across metamagnetic transitions.

Highlights

Tuning of electronic density-of-states singularities is a common route to unconventional metal physics
A van Hove singularity (VHS) is found in high-temperature cuprate superconductors, and recently it has been associated with the onset of the mysterious pseudogap phase[4,5]
This results in a five-fold variation of the Kadowaki–Woods ratio across the metamagnetic transition

Summary

Introduction

Tuning of electronic density-of-states singularities is a common route to unconventional metal physics. Fermi liquid properties persist across the metamagnetic transition, but with an unusually strong variation of the Kadowaki-Woods ratio This is revealed by a strong decoupling of inelastic electron scattering and electronic mass inferred from densityof-state probes. We discuss this Fermi liquid behavior in terms of a magnetic field tunable van Hove singularity in the presence of disorder. Despite the expected connection between an ideal VHS and unconventional electronic properties observed in a wide range of materials, the effect of disorder and dimensionality has received little attention. Quasiparticles in layered materials are neither constrained perfectly in two dimensions nor are their lifetime infinite Both effects, dimensionality and disorder or electron correlations, broaden the DOS anomaly[19] and potentially change the ideal VHS physics substantially. The role of dimensionality and disorder in the context of VHS physics is discussed along with possible multiband scenarios for the strong variation of the Kadowaki–Woods ratio

Methods

Results

Conclusion