Kondo-coupled van der Waals antiferromagnet with high-mobility quasiparticles

TL;DR

This study reveals that CeTe$_3$, a Kondo-coupled van der Waals antiferromagnet, exhibits high quasiparticle mobility despite effective mass enhancement, due to topological protection, making it promising for advanced electronic applications.

Contribution

The paper demonstrates the coexistence of high mobility and strong electronic correlations in CeTe$_3$, a Kondo-coupled vdW antiferromagnet, with mobility increasing despite mass renormalization.

Findings

Effective mass is significantly enhanced at low temperature.

Quantum mobility reaches ~2403 cm$^2$/Vs in bulk and ~3158 cm$^2$/Vs in nanoflakes.

High mobility persists despite strong correlation effects.

Abstract

Two-dimensional van der Waals (vdW) materials exhibit high carrier mobility and tunability, making them suitable for low-power, high-performance electronic and spintronic applications. Incorporating narrow-band electronic correlation effects could further promote tunability, though mass renormalization may impact carrier mobility. It is therefore challenging to identify a vdW material with both high mobility and strong correlation. Herein, by a combination of optical spectroscopy and high-field quantum-oscillation measurements, we observe significant effective-mass enhancement in CeTe$_3$ at low temperature, arising from not only the band-structure modulation by antiferromagnetic ordering but also the narrow-band correlation effect. Despite the mass enhancement, the quantum mobility surprisingly \textit{increases} and reaches $\sim$2403 cm$^2$/Vs, likely benefiting from topological protection. Remarkably, these unique properties are maintained in atomically thin nanoflakes with quantum mobility enhanced to $\sim$3158 cm$^2$/Vs. Thus, CeTe$_3$ emerges as a promising Kondo-coupled vdW antiferromagnetic metal with high-mobility quasiparticles, potentially unlocking new device concepts.