Electronic anisotropy and rotational symmetry breaking at a Weyl semimetal/spin ice interface

TL;DR

This study uncovers electronic anisotropy and symmetry breaking at a heterostructure interface between a Weyl semimetal and spin ice, revealing complex quantum phenomena driven by magnetic fields and interfacial interactions.

Contribution

It demonstrates for the first time the emergence of interfacial anisotropy and symmetry breaking in a Weyl semimetal/spin ice heterostructure, highlighting novel quantum effects.

Findings

Six-fold anisotropic transport response under magnetic fields

Field-tuned magnetism induces electron scattering in topological states

Observation of a two-fold anisotropic response indicating a new many-body state

Abstract

In magnetic pyrochlore materials, the interplay of spin-orbit coupling, electronic correlations, and geometrical frustration gives rise to exotic quantum phases, including topological semimetals and spin ice. While these phases have been observed in isolation, the interface-driven phenomena emerging from their interaction have never been realized previously. Here, we report on the discovery of interfacial electronic anisotropy and rotational symmetry breaking at a heterostructure consisting of the Weyl semimetal Eu2Ir2O7 and spin ice Dy2Ti2O7. Subjected to magnetic fields, we unveil a six-fold anisotropic transport response that is theoretically accounted by a Kondo-coupled heterointerface, where the spin ice's field-tuned magnetism induces electron scattering in the Weyl semimetal's topological Fermi-arc states. Furthermore, at elevated magnetic fields, we reveal a two-fold anisotropic response indicative of a new symmetry-broken many-body state. This discovery showcases the nascent potential of complex quantum architectures in search of emergent phenomena unreachable in bulk crystals.