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arXiv · 1702.07455

Quantum spin ice under a [111] magnetic field: from pyrochlore to kagomé

Troels Arnfred Bojesen·Shigeki Onoda
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Abstract

Quantum spin ice, modeled for magnetic rare-earth pyrochlores, has attracted great interest for hosting a U(1) quantum spin liquid, which involves spin-ice monopoles as gapped deconfined spinons, as well as gapless excitations analogous to photons. However, the global phase diagram under a [111] magnetic field remains open. Here we uncover by means of unbiased quantum Monte-Carlo simulations that a supersolid of monopoles, showing both a superfluidity and a partial ionization, intervenes the kagomé spin ice and a fully ionized monopole insulator, in contrast to classical spin ice where a direct discontinuous phase transition takes place. We also show that on cooling, kagomé spin ice evolves towards a valence bond solid similar to what appears in the associated kagomé lattice model [S. V. Isakov et al., Phys. Rev. Lett. 97, 147202 (2006)]. Possible relevance to experiments is discussed.

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Troels Arnfred Bojesen, Shigeki Onoda. 2017-10-16. Quantum spin ice under a [111] magnetic field: from pyrochlore to kagomé. https://doi.org/10.1103/physrevlett.119.227204

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