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arXiv:2308.00249

Spin dynamics of the $E_8$ particles

Xiao Wang, K. Puzniak, K. Schmalzl, Christian Balz, Masaaki Matsuda, Akira Okutani, Masayuki Hagiwara, Jie Ma, Jianda Wu, B. Lake

Published Aug 1, 2023• 1 citation
arXivHTMLPDF

Abstract

In this article, we report on inelastic neutron scattering measurements on a quasi-1D antiferromagnet BaCo$_2$V$_2$O$_8$ under a transverse magnetic field applied along the (0,1,0) direction. Combining results of inelastic neutron scattering experiments, analytical analysis, and numerical simulations, we precisely studied the $E_8$ excitations appearing in the whole Brillouin zone at $B_c^{1D}\approx 4.7$ T. The energy scan at $Q=(0,0,2)$ reveals a match between the data and the theoretical prediction of energies of multiple $E_8$ excitations. Furthermore, dispersions of the lightest three $E_8$ particles have been clearly observed, confirming the existence of the $E_8$ particles in BaCo$_2$V$_2$O$_8$. Our results lay down a concrete ground to systematically study the physics of the exotic $E_8$ particles.

DOI
10.48550/arxiv.2308.00249

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