A Large-$S$ Study of Quantum Kagome Ice

TL;DR

This paper investigates a quantum spin ice model on the kagome lattice using large-$S$ expansion, confirming the presence of disordered lobes consistent with previous Quantum Monte Carlo findings, and providing insights into its phase diagram.

Contribution

It applies large-$S$ expansion to analyze the quantum kagome ice model, complementing prior QMC results and elucidating its phase structure.

Findings

Disordered lobes of quantum spin liquid phase identified

Large-$S$ ground state phase diagram matches QMC trends

Confirmation of disordered phases in the model

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.