Topological antichiral surface states in a magnetic Weyl photonic crystal

Autor: Xiang Xi, Bei Yan, Linyun Yang, Yan Meng, Zhen-Xiao Zhu, Jing-Ming Chen, Ziyao Wang, Peiheng Zhou, Perry Ping Shum, Yihao Yang, Hongsheng Chen, Subhaskar Mandal, Gui-Geng Liu, Baile Zhang, Zhen Gao
Přispěvatelé: School of Physical and Mathematical Sciences, Centre for Disruptive Photonic Technologies (CDPT), The Photonics Institute
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Popis: Chiral edge states that propagate oppositely at two parallel strip edges are a hallmark feature of Chern insulators which were first proposed in the celebrated two-dimensional (2D) Haldane model. Subsequently, counterintuitive antichiral edge states that propagate in the same direction at two parallel strip edges were discovered in a 2D modified Haldane model. Recently, chiral surface states, the 2D extension of one-dimensional (1D) chiral edge states, have also been observed in a photonic analogue of a 3D Haldane model. However, despite many recent advances in antichiral edge states and chiral surface states, antichiral surface states, the 2D extension of 1D antichiral edge states, have never been realized in any physical system. Here, we report the experimental observation of antichiral surface states by constructing a 3D modified Haldane model in a magnetic Weyl photonic crystal with two pairs of frequency-shifted Weyl points (WPs). The 3D magnetic Weyl photonic crystal consists of gyromagnetic cylinders with opposite magnetization in different triangular sublattices of a 3D honeycomb lattice. Using microwave field-mapping measurements, unique properties of antichiral surface states have been observed directly, including the antichiral robust propagation, tilted surface dispersion, a single open Fermi arc connecting two projected WPs and a single Fermi loop winding around the surface Brillouin zone (BZ). These results extend the scope of antichiral topological states and enrich the family of magnetic Weyl semimetals. Ministry of Education (MOE) Nanyang Technological University National Research Foundation (NRF) Published version Z.G. acknowledges support from the National Natural Science Foundation of China under Grant No. 12104211, Shenzhen Science and Technology Innovation Commission under Grant No. 20220815111105001, and SUSTech under Grant No. Y01236148 and No. Y01236248. Work at Nanyang Technological University was sponsored by Singapore Ministry of Education Academic Research Fund Tier 3 Grant MOE2016-T3-1-006, and the National Research Foundation Competitive Research Program NRF-CRP23-2019-0007. Work at Zhejiang University was sponsored by the National Natural Science Foundation of China under grant number 62175215 and the Fundamental Research Funds for the Central Universities (2021FZZX001-19).
Databáze: OpenAIRE