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arXiv · 0907.2536

Quantum Melting of Spin Ice: Emergent Cooperative Quadrupole and Chirality

Shigeki Onoda·Yoichi Tanaka
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Abstract

A quantum melting of the spin ice is proposed for pyrochlore-lattice magnets Pr$_2TM_2$O$_7$ ($TM=$Ir, Zr, and Sn). The quantum superexchange Hamiltonian having a nontrivial magnetic anisotropy is derived in the basis of atomic non-Kramers magnetic doublets. The ground states exhibit a cooperative ferroquadrupole and pseudospin chirality, forming a magnetic analog of smectic liquid crystals. Our theory accounts for dynamic spin-ice behaviors experimentally observed in Pr$_2TM_2$O$_7$.

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Shigeki Onoda, Yoichi Tanaka. 2010-06-27. Quantum Melting of Spin Ice: Emergent Cooperative Quadrupole and Chirality. https://doi.org/10.1103/physrevlett.105.047201

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