Ultrasensitive terahertz sensing with high-Q Fano resonances in metasurfaces
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- 27 October 2014
- journal article
- research article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 105 (17), 171101
- https://doi.org/10.1063/1.4895595
Abstract
High quality factor resonances are extremely promising for designing ultra-sensitive refractive index label-free sensors, since it allows intense interaction between electromagnetic waves and the analyte material. Metamaterial and plasmonic sensing have recently attracted a lot of attention due to subwavelength confinement of electromagnetic fields in the resonant structures. However, the excitation of high quality factor resonances in these systems has been a challenge. We excite an order of magnitude higher quality factor resonances in planar terahertz metamaterials that we exploit for ultrasensitive sensing. The low-loss quadrupole and Fano resonances with extremely narrow linewidths enable us to measure the minute spectral shift caused due to the smallest change in the refractive index of the surrounding media. We achieve sensitivity levels of 7.75 × 103 nm/refractive index unit (RIU) with quadrupole and 5.7 × 104 nm/RIU with the Fano resonances which could be further enhanced by using thinner substrates. These findings would facilitate the design of ultrasensitive real time chemical and biomolecular sensors in the fingerprint region of the terahertz regime.Keywords
Funding Information
- NTU start up grant
This publication has 39 references indexed in Scilit:
- Superconductor photonicsNature Photonics, 2014
- The Fano Resonance in Symmetry Broken Terahertz MetamaterialsIEEE Transactions on Terahertz Science and Technology, 2013
- From metamaterials to metadevicesNature Materials, 2012
- Low-loss ultra-high-Q dark mode plasmonic Fano metamaterialsOptics Letters, 2012
- Low-Loss Plasmonic MetamaterialsScience, 2011
- Metamaterials: a new frontier of science and technologyChemical Society Reviews, 2011
- Loss-free and active optical negative-index metamaterialsNature, 2010
- Sharp Trapped-Mode Resonances in Planar Metamaterials with a Broken Structural SymmetryPhysical Review Letters, 2007
- Optical negative-index metamaterialsNature Photonics, 2007
- Negative‐Index Materials: New Frontiers in OpticsAdvanced Materials, 2006