Indexed by: Journal paper

Journal: Photonics Research

Included Journals: SCI

Affiliation of Author(s): 华中科技大学

Place of Publication: 中国

Discipline: 物理学

Funded by: 国基金

Document Type: J

Volume: 13

Issue: 1

Page Number: 113-123

ISSN No.: 2327-9125

Date of Publication: 2024-12-20

Impact Factor: 6.6

Teaching and Research Group: 武汉光电国家研究中心

Abstract: Artificially designed hyperbolic metamaterials (HMMs) with extraordinary optical anisotropy can support highly sensitive plasmonic sensing detections, showcasing significant potential for advancements in medical research and clinical diagnostics. In this study, we develop a gold nanoridge HMM and disclose the plasmonic sensing physical mechanism based on this type of HMM through theoretical and experimental studies. We determine that the high modal group velocity of plasmonic guided modes stemming from a large transverse permittivity of HMMs directly results in high sensitivity. By combining electron-beam lithography, oxygen plasma etching, and electroplating, the fabricated gold nanoridge array possesses an extremely high structural filling ratio that is difficult to obtain through conventional processes. This leads to a large transverse permittivity and enables highly confined and ultra-sensitive bulk plasmon–polariton (BPP) guided modes. By exciting these modes in the visible to near-infrared region, we achieve a record sensitivity of 53,300 nm/RIU and a figure of merit of 533. Furthermore, the developed plasmonic nanoridge HMM sensor exhibits an enhanced sensitivity of two orders of magnitude compared to that of the same type of HMM sensor in label-free biomolecule detection. Our study not only offers a promising avenue for label-free biosensing but also holds great potential to enhance early disease detection and monitoring.