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arXiv · 2206.10647

Field-induced Kitaev multipolar liquid in spin-orbit coupled $d^{2}$ honeycomb Mott insulators

Ahmed Rayyan·Derek Churchill·Hae-Young Kee
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Abstract

The Kitaev model, characterized by bond-dependent Ising spin interactions among spin-orbit entangled dipole moments in Mott insulators, offered a new approach to quantum spin liquids. Motivated by another type of bond-dependent interaction among quadrupole moments in $5d^2$ Mott insulators, we provide a microscopic route to uncover the Kitaev multipolar liquid, featuring fractionalized excitations out of non-Kramers doublets carrying multipole moments. The key ingredient is the magnetic field that allows for bond-anisotropic quadrupole-octupole interactions via mixing with the excited triplet states. The conditions to realize signatures of this phase in real materials are also discussed.

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Ahmed Rayyan, Derek Churchill, Hae-Young Kee. 2022-06-21. Field-induced Kitaev multipolar liquid in spin-orbit coupled $d^{2}$ honeycomb Mott insulators. https://doi.org/10.1103/physrevb.107.l020408

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