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arXiv · 1711.03778

How many spin liquids are there in Ca$_{10}$Cr$_7$O$_{28}$?

Rico Pohle·Han Yan·Nic Shannon
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Abstract

The search for novel phases of matter is a central theme of modern physics, with some of the most intriguing examples provided by the spin liquids found in magnets with competing, or "frustrated" interactions. Ca$_{10}$Cr$_7$O$_{28}$, a novel spin-$1/2$ magnet with a bilayer breathing-kagome lattice, has properties which differ from from any known spin liquid. However, understanding Ca$_{10}$Cr$_7$O$_{28}$ presents a significant challenge, because of its complex frustration. Here we use large-scale molecular-dynamics simulation to explore the origin of spin-liquid behaviour in Ca$_{10}$Cr$_7$O$_{28}$. We uncover qualitatively different behaviour on different timescales, and argue that ground state of Ca$_{10}$Cr$_7$O$_{28}$ is born out of a slowly-fluctuating "spiral spin liquid", while faster fluctuations echo the U(1) spin liquid found in the kagome antiferromagnet. These results provide a concrete scenario for spin-liquid behaviour in Ca$_{10}$Cr$_7$O$_{28}$, and highlight the possibility of spin liquids existing on multiple timescales.

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Rico Pohle, Han Yan, Nic Shannon. 2017-11-10. How many spin liquids are there in Ca$_{10}$Cr$_7$O$_{28}$?. https://doi.org/10.1103/physrevb.104.024426

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