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arXiv · 2206.01392

Quasi-2D anomalous Hall Mott insulator of topologically engineered Jeff =1/2 electrons

Junyi Yang·Hidemaro Suwa·Derek Meyers·Han Zhang·Lukas Horak·Zhaosheng Wang·Gilberto Fabbris·Yongseong Choi·Jenia Karapetrova·Jong-Woo Kim·Daniel Haskel·Philip J. Ryan·M. P. M. Dean·Lin Hao·Jian Liu
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Abstract

We investigate an experimental toy-model system of a pseudospin-half square-lattice Hubbard Hamiltonian in [(SrIrO3)1/(CaTiO3)1] to include both nontrivial complex hopping and moderate electronic correlation. While the former induces electronic Berry phases as anticipated from the weak-coupling limit, the later stabilizes an antiferromagnetic (AFM) Mott insulator ground state in analogous to the strong-coupling limit. Their combined results in the real system are found to be an anomalous Hall effect with a non-monotonic temperature dependence due to the self-competition of the electron-hole pairing in the Mott state, and an exceptionally large Ising anisotropy that is captured as a giant magnon gap beyond the superexchange approach. The unusual phenomena highlight the rich interplay of electronic topology and electronic correlation in the intermediate-coupling regime that is largely unexplored and challenging in theoretical modelling.

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Junyi Yang, Hidemaro Suwa, Derek Meyers, Han Zhang, Lukas Horak, Zhaosheng Wang, Gilberto Fabbris, Yongseong Choi, Jenia Karapetrova, Jong-Woo Kim, Daniel Haskel, Philip J. Ryan, M. P. M. Dean, Lin Hao, Jian Liu. 2022-06-03. Quasi-2D anomalous Hall Mott insulator of topologically engineered Jeff =1/2 electrons. https://doi.org/10.1103/physrevx.12.031015

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