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arXiv · 2102.02818

Fingerprinting Triangular-Lattice Antiferromagnet by Excitation Gaps

K. E. Avers·P. A. Maksimov·P. F. S. Rosa·S. M. Thomas·J. D. Thompson·W. P. Halperin·R. Movshovich·A. L. Chernyshev
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Abstract

CeCd$_3$As$_3$ is a rare-earth triangular-lattice antiferromagnet with large inter-layer separation. Our field-dependent heat capacity measurements at dilution fridge temperatures allow us to trace the field-evolution of the spin-excitation gaps throughout the antiferromagnetic and paramagnetic regions. The distinct gap evolution places strong constraints on the microscopic pseudo-spin model, which, in return, yields a close {\it quantitative} description of the gap behavior. This analysis provides crucial insights into the nature of the magnetic state of CeCd$_3$As$_3$, with a certainty regarding its stripe order and low-energy model parameters that sets a compelling paradigm for exploring and understanding the rapidly growing family of the rare-earth-based triangular-lattice systems.

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K. E. Avers, P. A. Maksimov, P. F. S. Rosa, S. M. Thomas, J. D. Thompson, W. P. Halperin, R. Movshovich, A. L. Chernyshev. 2021-02-04. Fingerprinting Triangular-Lattice Antiferromagnet by Excitation Gaps. https://doi.org/10.1103/physrevb.103.l180406

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