• Photonics Research
  • Vol. 10, Issue 8, 1828 (2022)
Chen Zhao1、2, Guangwei Hu2, Yang Chen2, Qing Zhang2, Yongzhe Zhang1、3、*, and Cheng-Wei Qiu2、4、*
Author Affiliations
  • 1Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, China
  • 2Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore
  • 3e-mail: yzzhang@bjut.edu.cn
  • 4e-mail: chengwei.qiu@nus.edu.sg
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    DOI: 10.1364/PRJ.459383 Cite this Article Set citation alerts
    Chen Zhao, Guangwei Hu, Yang Chen, Qing Zhang, Yongzhe Zhang, Cheng-Wei Qiu. Unidirectional bound states in the continuum in Weyl semimetal nanostructures[J]. Photonics Research, 2022, 10(8): 1828 Copy Citation Text show less

    Abstract

    Recently studied bound states in the continuum (BICs) enable perfect localization of light and enhance light–matter interactions although systems are optically open. They have found applications in numerous areas, including optical nonlinearity, light emitters, and nano-sensors. However, their unidirectional nature in nonreciprocal devices is still elusive because such trapping states are easily destroyed when the symmetry of an optical system is broken. Herein, we propose nonreciprocal and dynamically tunable BICs for unidirectional confinement of light and symmetry-protected BICs at Γ-point by introducing antiparallel magnetism into the optical system. We demonstrate that such BICs can be achieved by using topological magnetic Weyl semimetals near zero-index frequency without any structural asymmetry, and are largely tunable via modifying the Fermi level. Our results reveal a regime of extreme light manipulation and interaction with emerging quantum materials for various practical applications.
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    Ψ(kx)Ψ(kx)eikycdcΦ(kx)Φ(kx)eikycdc=0.(B5)

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    Chen Zhao, Guangwei Hu, Yang Chen, Qing Zhang, Yongzhe Zhang, Cheng-Wei Qiu. Unidirectional bound states in the continuum in Weyl semimetal nanostructures[J]. Photonics Research, 2022, 10(8): 1828
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