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arXiv · 2108.07816

Probing Flat Band Physics in Spin Ice Systems via Polarized Neutron Scattering

Kristian Tyn Kai Chung·Jeremy Swee Kang Goh·Aritro Mukherjee·Wen Jin·Daniel Lozano-Gómez·Michel J. P. Gingras
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Abstract

In this paper, we illustrate how polarized neutron scattering can be used to isolate the spin-spin correlations of modes forming flat bands in a frustrated magnetic system hosting a classical spin liquid phase. In particular, we explain why the nearest-neighbor spin ice model, whose interaction matrix has two flat bands, produces a dispersionless (i.e. "flat") response in the non-spin-flip (NSF) polarized neutron scattering channel, and demonstrate that NSF scattering is a highly sensitive probe of correlations induced by weak perturbations which lift the flat band degeneracy. We use this to explain the experimentally measured dispersive (i.e. non-flat) NSF channel of the dipolar spin ice compound $\mathrm{Ho}_2 \mathrm{Ti}_2 \mathrm{O}_7$.

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Kristian Tyn Kai Chung, Jeremy Swee Kang Goh, Aritro Mukherjee, Wen Jin, Daniel Lozano-Gómez, Michel J. P. Gingras. 2021-08-17. Probing Flat Band Physics in Spin Ice Systems via Polarized Neutron Scattering. https://doi.org/10.1103/physrevlett.128.107201

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