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arXiv · 2203.01612

Magnetic field tuning of the valley population in the Weyl phase of Nd$_2$Ir$_2$O$_7$

Itzik Kapon·Carl Willem Rischau·Bastien Michon·Kai Wang·Bing Xu·Qiu Yang·Satoru Nakatsuji·Dirk van der Marel
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Abstract

The frustrated magnet Nd$_2$Ir$_2$O$_7$, where strong correlations together with spin-orbit coupling play a crucial role, is predicted to be a Weyl semimetal and to host topological pairs of bulk Dirac-like valleys. Here we use an external magnetic field to manipulate the localized rare earth 4f moments coupled to the 5d electronic bands. Low energy optical spectroscopy reveals that a field of only a few teslas suffices to create charge compensating pockets of holes and electrons in different regions of momentum space, thus introducing a valley population shift that can be tuned with the field.

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Itzik Kapon, Carl Willem Rischau, Bastien Michon, Kai Wang, Bing Xu, Qiu Yang, Satoru Nakatsuji, Dirk van der Marel. 2022-03-03. Magnetic field tuning of the valley population in the Weyl phase of Nd$_2$Ir$_2$O$_7$. https://doi.org/10.1103/physrevresearch.4.023056

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