Configurable topological beam separation via a

picture: fig. 1 | Construction of an antichiral gyromagnetic photonic crystal. (a) Schematic illustration of an antichiral gyromagnetic photonic crystal. (b) The first Brillouin zone of the honeycomb network. (c) Unmagnetized gyromagnetic photonic crystal. (d)

picture: fig. 1 | Construction of an antichiral gyromagnetic photonic crystal. (a) Schematic illustration of an antichiral gyromagnetic photonic crystal. (b) The first Brillouin zone of the honeycomb network. (c) Unmagnetized gyromagnetic photonic crystal. (d) Uniformly magnetized gyromagnetic photonic crystal. (e) Compound magnetized gyromagnetic photonic crystal.
see After

Credit: OAE

A new publication from Opto-electronic science; DO I 10.29026/oes.2022.220001 Configurable topological beam splitting via an antichiral gyromagnetic photonic crystal.

Topological insulators, whose bulky states are forbidden while surface/edge states are conductive and topologically protected. In particular, recent advances in topologically protected edge states have attracted increasing attention in the optics and photonics community. In 2008, Raghu and Haldane first theoretically predicted that the topologically protected chiral unidirectional edge state can be created by analogy with the integer quantum Hall effect in a two-dimensional electron gas system, where the unidirectional edge states propagate in opposite directions to two parallel edges of a gyromagnetic photonic crystal [Phys. Rev. Lett. 100, 013904 (2008)]. In 2020, Professor Zhi-Yuan Li’s research group from South China University of Technology theoretically proposed another intriguing case where unidirectional edge states with two opposite parallel zigzag edges can propagate in the same direction , and they are called antichirals. one-way edge states [Phys. Rev. B 101, 214102 (2020)]. To date, antichiral unidirectional edge states have been studied in various fermionic and bosonic systems, however, many studies have only focused on demonstrating the antichiral unidirectional transport property, and few of them touch on the properties. unique antichiral topological systems and new applications.

This paper reports the construction and observation of the topological beam splitting with the easily adjustable right-left ratio in an antichiral gyromagnetic photonic crystal. The splitter is compact and configurable, has high transmission efficiency, enables multi-channel use, resists crosstalk, and is robust against faults and obstacles. This performance is attributed to the particular property that antichiral unidirectional edge states only exist at the zigzag edge but not at the chair edge of the antichiral gyromagnetic photonic crystal. When combining two rectangular antichiral gyromagnetic photonic crystals respectively containing left and right propagating antichiral unidirectional edge states, bidirectionally radiating unidirectional edge states on two parallel zigzag edges can be obtained. Finally, they design a topological beam splitter with a configurable splitting ratio that is easy to tune by simply changing the source excitation condition. These observations can enrich the understanding of fundamental physics and broaden topological photonic applications.

Article reference Chen JF, Li ZY. Configurable topological beam splitting via an antichiral gyromagnetic photonic crystal. Opto-electron Sci 1, 220001 (2022). do I: 10.29026/oes.2022.220001

Key words: topological photonics / unidirectional edge state / photonic crystal / beam splitting / topological materials

# # # # # #

The “Artificial Light and Acoustic Microstructure” research team led by world-cited scientist Professor Li Zhi-Yuan of South China University of Technology currently has 5 professors, 4 associate professors and 42 master’s researchers, doctorate and post-doctorate. The team is primarily engaged in the theories, experimental and applied research of micro-nano photonics and its intersection with nonlinear optics, laser technology, photophysics, quantum physics, as well as the intersection of photonic crystals /phononic, optical/acoustic and topological metamaterials. physics, and other important international borders and national needs. Many of the team’s papers have been selected as ESI Hot Papers or Highly Cited Papers. The team has undertaken nearly 20 major projects for the introduction of innovative and entrepreneurial teams in Guangdong Province, key research and development projects of the Ministry of Science and Technology, key, general and youth programs of the National Foundation of China, key research and development projects. projects in Guangdong province and outstanding youth projects in Guangdong province.

# # # # # #

Opto-electronic science (OES) is an international, interdisciplinary, peer-reviewed, open access journal published by the Institute of Optics and Electronics of the Chinese Academy of Sciences as a sister journal of Advances in optoelectronics (OEA, FI=9.682). OES is dedicated to providing a professional platform to promote academic exchange and accelerate innovation. OES publishes articles, reviews and letters on fundamental breakthroughs in the basic science of optics and optoelectronics.

# # # # # #

More information: https://www.oejournal.org/oes

Editorial Board: https://www.oejournal.org/oes/editorialboard/list

OES is available on OE journals (https://www.oejournal.org/oes/archive)

OES submission can be done using ScholarOne (https://mc03.manuscriptcentral.com/oes)

CN 51-1800/O4

ISSN 2097-0382

Contact us: [email protected]

Twitter: @OptoElectronAdv (https://twitter.com/OptoElectronAdv?lang=en)

WeChat: OE_Journal

# # # # # #


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of press releases posted on EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.