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arXiv · 1512.03930

A Large-$S$ Study of Quantum Kagome Ice

S. A. Owerre·A. A. Burkov·Roger G. Melko
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Abstract

We present a large-$S$ study of a quantum spin ice Hamiltonian, introduced by Huang, et al., [PRL 112, 167203 (2014)], on the kagome lattice. This model involves a competition between the frustrating Ising term of classical kagome ice, a Zeeman magnetic field $h$,and a nearest-neighbor transverse spin-flip term $S^x_iS^x_j - S^y_iS^y_j$. Recent Quantum Monte Carlo (QMC) simulations by Carrasquilla, et al., [Nature Communications, 6, 7421, (2015)], uncovered lobes of a disordered phase for large Ising interaction and $h\neq 0$ -- a putative quantum spin liquid phase. Here, we examine the nature of this model using large-$S$ expansion. We show that the ground state properties generally have the same trends with those observed in QMC simulations. In particular, the large-$S$ ground state phase diagram captures the existence of the disordered lobes.

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S. A. Owerre, A. A. Burkov, Roger G. Melko. 2016-03-18. A Large-$S$ Study of Quantum Kagome Ice. https://doi.org/10.1103/physrevb.93.144402

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