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arXiv · 1810.00815

Monoclinic SrIrO$_3$ - A Dirac semimetal produced by non-symmorphic symmetry and spin-orbit coupling

T. Takayama·A. N. Yaresko·H. Takagi
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Abstract

SrIrO$_3$ crystallizes in a monoclinic structure of distorted hexagonal perovskite at ambient pressure. The transport measurements show that the monoclinic SrIrO$_3$ is a low-carrier density semimetal, as in the orthorhombic perovskite polymorph. The electronic structure calculation indicates a semimetallic band structure with Dirac bands at two high-symmetry points of Brillouin zone only when spin-orbit coupling is incorporated, suggesting that the semimetallic state is produced by the strong spin-orbit coupling. We argue that the Dirac bands are protected by the non-symmorphic symmetry of lattice.

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T. Takayama, A. N. Yaresko, H. Takagi. 2018-10-01. Monoclinic SrIrO$_3$ - A Dirac semimetal produced by non-symmorphic symmetry and spin-orbit coupling. https://doi.org/10.1088/1361-648x%2Faaf68a

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