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arXiv · 2409.18880

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

Tsung-Chi Wu·Yueqing Chang·Ang-Kun Wu·Michael Terilli·Fangdi Wen·Mikhail Kareev·Eun Sang Choi·David Graf·Qinghua Zhang·Lin Gu·Zhentao Wang·Jedediah H. Pixley·Jak Chakhalian
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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.

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Tsung-Chi Wu, Yueqing Chang, Ang-Kun Wu, Michael Terilli, Fangdi Wen, Mikhail Kareev, Eun Sang Choi, David Graf, Qinghua Zhang, Lin Gu, Zhentao Wang, Jedediah H. Pixley, Jak Chakhalian. 2024-09-27. Electronic anisotropy and rotational symmetry breaking at a Weyl semimetal/spin ice interface. https://arxiv.org/abs/2409.18880

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