Saved in:
Bibliographic Details
Main Authors: Guo, Junhui, Dong, Bing, Zhang, Eryong, Tu, Qing-An, He, Xiaoyong, Wu, Xichuan, Liu, Mingjing, Gong, Maohua, Meng, Yan, Xi, Xiang, Wang, Hongcheng, Gao, Zhen
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2604.01772
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918485646376960
author Guo, Junhui
Dong, Bing
Zhang, Eryong
Tu, Qing-An
He, Xiaoyong
Wu, Xichuan
Liu, Mingjing
Gong, Maohua
Meng, Yan
Xi, Xiang
Wang, Hongcheng
Gao, Zhen
author_facet Guo, Junhui
Dong, Bing
Zhang, Eryong
Tu, Qing-An
He, Xiaoyong
Wu, Xichuan
Liu, Mingjing
Gong, Maohua
Meng, Yan
Xi, Xiang
Wang, Hongcheng
Gao, Zhen
contents The terahertz (THz) spectral regime offers unique opportunities for next-generation biochemical sensing due to its non-destructive, label-free probing capability and strong sensitivity to molecular vibrations. However, conventional THz biosensors remain hampered by intrinsically low-quality factors and limited sensitivity, severely restricting their utility for trace-level biochemical and chemical detection. Here, we report an ultrasensitive THz metasurface biosensor that harnesses quasi-bound states in the continuum (QBICs) with sharp resonances and enhanced light-matter interactions to overcome these limitations. As a proof of concept, the device achieves label-free detection of a sulfur-containing amino acid cysteine, with an ultrahigh sensitivity of 492 GHz/RIU and an ultralow detection limit down to 0.00025 mg/mL. The synergy between QBIC-induced field confinement and meticulous structural optimization of the metasurface underpins this performance, marking a significant advance over conventional THz metasurface biosensing schemes. These results establish QBIC-based metasurfaces as a promising platform for ultrasensitive and high-precision biochemical and chemical sensing, with broad implications for medical diagnostics, food safety, and environmental monitoring.
format Preprint
id arxiv_https___arxiv_org_abs_2604_01772
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Ultrasensitive Terahertz Metasurface Biosensor Based on Quasi-Bound States in the Continuum
Guo, Junhui
Dong, Bing
Zhang, Eryong
Tu, Qing-An
He, Xiaoyong
Wu, Xichuan
Liu, Mingjing
Gong, Maohua
Meng, Yan
Xi, Xiang
Wang, Hongcheng
Gao, Zhen
Optics
The terahertz (THz) spectral regime offers unique opportunities for next-generation biochemical sensing due to its non-destructive, label-free probing capability and strong sensitivity to molecular vibrations. However, conventional THz biosensors remain hampered by intrinsically low-quality factors and limited sensitivity, severely restricting their utility for trace-level biochemical and chemical detection. Here, we report an ultrasensitive THz metasurface biosensor that harnesses quasi-bound states in the continuum (QBICs) with sharp resonances and enhanced light-matter interactions to overcome these limitations. As a proof of concept, the device achieves label-free detection of a sulfur-containing amino acid cysteine, with an ultrahigh sensitivity of 492 GHz/RIU and an ultralow detection limit down to 0.00025 mg/mL. The synergy between QBIC-induced field confinement and meticulous structural optimization of the metasurface underpins this performance, marking a significant advance over conventional THz metasurface biosensing schemes. These results establish QBIC-based metasurfaces as a promising platform for ultrasensitive and high-precision biochemical and chemical sensing, with broad implications for medical diagnostics, food safety, and environmental monitoring.
title Ultrasensitive Terahertz Metasurface Biosensor Based on Quasi-Bound States in the Continuum
topic Optics
url https://arxiv.org/abs/2604.01772