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arXiv · 2202.09984

Experimental signatures of versatile Weyl semimetal in pyrochlore iridate with spin-ice like magnetic orders

Kentaro Ueda·Hiroaki Ishizuka·Markus Kriener·Shunsuke Kitou·Denis Maryenko·Minoru Kawamura·Taka-hisa Arima·Masashi Kawasaki·Yoshinori Tokura
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Abstract

We report experimental signatures of topological transitions among the Weyl semimetal states of pyrochlore Pr2Ir2O7, where the Kondo coupling between the Ir topological electrons and the spin-ice like orders of Pr moments plays a decisive role. The magnetic-field dependence of resistivity and the Hall conductivity exhibits a plateau and a sharp jump associated with a magnetic-field hysteresis, similar to a liquid-gas-like transition in dipolar spin ice system. Furthermore, the Kondo coupling is controlled by the hydrostatic pressure, revealing that the field-induced displacement of Weyl points in the momentum space strongly depends on the respective electronic state as well as on the Kondo coupling strength. These observations pave a route toward the engineering of band topology in hybrid quantum materials with relativistic conduction electrons and localized magnetic moments.

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Kentaro Ueda, Hiroaki Ishizuka, Markus Kriener, Shunsuke Kitou, Denis Maryenko, Minoru Kawamura, Taka-hisa Arima, Masashi Kawasaki, Yoshinori Tokura. 2022-02-21. Experimental signatures of versatile Weyl semimetal in pyrochlore iridate with spin-ice like magnetic orders. https://doi.org/10.1103/physrevb.105.l161102

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