Emergent correlated topological phases in Weyl semimetal/spin ice pyrochlore heterostructures

In pyrochlore lattice materials, the interplay of electronic correlations, spin-orbit coupling, and geometrical frustration gives rise to exotic topological and strongly correlated states, including topological semimetals and spin ice. While these states have been observed in isolation, the interface-driven phases and phenomena emerging from their interactions have never been realized previously. In this talk, we report on the discovery of emergent electronic anisotropy and rotational symmetry breaking at the interface of a pyrochlore 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 the emergence of a new correlated topological phase. The discovery showcases the potential of frustrated magnets/topological semimetals pyrochlore heterostructures in search of emergent correlated topological phases that would otherwise be impossible to materialize.