Optical anisotropy of Bi<sub>2</sub>SeO<sub>5</sub> and near-field characterization of its waveguide modes
Anisotropic van der Waals (vdW) materials have attracted increasing attention in nanophotonics due to their unique optical properties. As a stable vdW material with a high dielectric constant (<i>κ</i>) and a wide bandgap, Bi<sub>2</sub>SeO<sub>5</sub> shows significant potential for semiconductor applications, but its optical properties have not been extensively studied. In this work, we first measured the refractive index of Bi<sub>2</sub>SeO<sub>5</sub> using an imaging spectroscopic ellipsometer and revealed its in-plane and out-of-plane anisotropy. Then, we studied the planar waveguide modes supported by Bi<sub>2</sub>SeO<sub>5</sub> flakes using photoemission electron microscopy (PEEM), showing good agreement with theoretical results of anisotropic waveguides. Near-field modes excited by ring slits were also studied and were significantly different from the simulated modes of isotropic materials. These results confirm the anisotropy of Bi<sub>2</sub>SeO<sub>5</sub>, suggesting its potential applications in nanophotonic and photoelectronic devices.
Authors
- Shufeng Wang (ORCID: https://orcid.org/0000-0003-3536-8000)
- Qinyun Liu
- Yaolong Li (ORCID: https://orcid.org/0000-0002-1457-190X)
- Pengzuo Jiang (ORCID: https://orcid.org/0000-0002-6359-3195)
- Xiaoyong Hu (ORCID: https://orcid.org/0000-0002-1545-1491)
- Guanyu Zhang (ORCID: https://orcid.org/0000-0002-3108-5604)
- Hailin Peng (ORCID: https://orcid.org/0000-0003-1569-0238)
- Hong Yang (ORCID: https://orcid.org/0000-0003-3459-4516)
- Qihuang Gong
- Yongchao Zhu (ORCID: https://orcid.org/0000-0001-9223-184X)
- Guowei Lü (ORCID: https://orcid.org/0000-0003-0646-6971)
- Xiaofang Li (ORCID: https://orcid.org/0000-0003-3788-5431)
- Yuxin Zhang (ORCID: https://orcid.org/0000-0002-2587-5239)
- Han Gao (ORCID: https://orcid.org/0009-0003-9536-6637)
- Jingyue Wang (ORCID: https://orcid.org/0000-0001-6897-6745)
- Mingjun Deng (ORCID: https://orcid.org/0000-0001-8562-0556)
- Jinglin Tang
- Zini Cao
- Jingying Xiao
Institutions
- Shanxi University (CN)
- Peking University (CN)
- Hefei University (CN)
- Beijing National Laboratory for Molecular Sciences (CN)
- Collaborative Innovation Center of Quantum Matter (CN)
- China University of Petroleum, East China (CN)
- Shandong Jianzhu University (CN)
Publication Details
- Journal
- Nanoscale
- Published
- 2025-01-01
- DOI
- https://doi.org/10.1039/d5nr00839e
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Natural Science Foundation of China
- National Key Research and Development Program of China