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arXiv · 1905.06866

Transition between canted antiferromagnetic and spin-polarized ferromagnetic quantum Hall states in graphene on a ferrimagnetic insulator

Y. Li·M. Amado·T. Hyart·G. P. Mazur·V. Risinggård·T. Wagner·L. McKenzie Sell·G. Kimbell·J. Wunderlich·J. Linder·J. W. A. Robinson
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Abstract

In the quantum Hall regime of graphene, antiferromagnetic and spin-polarized ferromagnetic states at the zeroth Landau level compete, leading to a canted antiferromagnetic state depending on the direction and magnitude of an applied magnetic field. Here, we investigate this transition at 2.7 K in graphene Hall bars that are proximity coupled to the ferrimagnetic insulator Y$_{3}$Fe$_{5}$O$_{12}$. From nonlocal transport measurements, we demonstrate an induced magnetic exchange field in graphene, which lowers the magnetic field required to modulate the magnetic state in graphene. These results show that a magnetic proximity effect in graphene is an important ingredient for the development of two-dimensional materials in which it is desirable for ordered states of matter to be tunable with relatively small applied magnetic fields (> 6 T).

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Y. Li, M. Amado, T. Hyart, G. P. Mazur, V. Risinggård, T. Wagner, L. McKenzie Sell, G. Kimbell, J. Wunderlich, J. Linder, J. W. A. Robinson. 2019-05-16. Transition between canted antiferromagnetic and spin-polarized ferromagnetic quantum Hall states in graphene on a ferrimagnetic insulator. https://doi.org/10.1103/physrevb.101.241405

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