Realization of the Single-pair-Weyl Phonons with the Maximum Charge Number in Acoustic Crystals

Abstract

To observe the Weyl phonon (WP) with the maximum charge and to design a realistic material structure containing only single-pair-WPs have long been considered two challenges in the field of topology physics. Here we have successfully designed an acoustic crystal to realize the single-pair-WPs with the maximum charge for the first time. Our theoretical simulations on acoustic band dispersions demonstrate that protected by the time-reversal symmetry ($\mathcal{T}$) and the point group symmetries, a WP with the charge -4 ($\mathcal{C}=-4$) and another WP with $\mathcal{C}=+4$ are located at the high-symmetry point $\Gamma$ and R, respectively, with the absence of any other kinds of WPs. Moreover, the singe-pair-WPs obtained here are designed by the simplest two-band mode, and the related quadruple-helicoid Fermi acrs can be observed clearly in experiments, since they aren't covered by any bulk bands and hybridized by other kinds of WPs. Our theoretical results provide a reliable acoustic crystal to study the topological properties of the single-pair-WPs with the maximum charge for experimentalists in this field.

7 pages; 4 figures

References in corpus (12)

• Anomalous Hall Effect in Weyl Metals
• Large Fermi Arcs in Unconventional Weyl Semimetal RhSi
• Weyl Semimetals, Fermi Arcs and Chiral Anomalies (A Short Review)
• Topological Nature of the Phonon Hall Effect
• Double-Weyl phonons in transition-metal monosilicides
• Spin fluctuation induced Weyl semimetal state in the paramagnetic phase of EuCd${}_2$As${}_2$
• A Single Pair of Weyl Fermions in Half-metallic EuCd2As2 Semimetal
• Twofold quadruple Weyl nodes in chiral cubic crystals
• Charge-4 Weyl point: Minimum lattice model and chirality-dependent properties
• Magnetic Weyl semimetal in K${}_2$Mn${}_3$(AsO${}_4$)${}_3$ with the minimum number of Weyl points
• Discovery of a maximally charged Weyl point
• Anisotropic three-dimensional quantum Hall effect and magnetotransport in mesoscopic Weyl semimetals

Cited by in corpus (1)

• Recipe for single-pair-Weyl-points phonons carrying the same chiral charges