title: Enhancement of localized surface plasmon resonance detection by incorporating metal-dielectric double-layered subwavelength gratings.
abstract: In this study, we investigated the enhanced sensing performance of a localized surface plasmon resonance (LSPR) biosensor by employing metal-dielectric double-layered subwavelength grating structures. The numerical results showed that the LSPR substrate with a dielectric spacer can provide not only a better sensitivity but also a significantly improved reflectance characteristic. While the presence of metallic gratings leads to a broad and shallow reflectance curve inevitably, the dielectric spacer can prevent the propagating surface plasmons from being interfered by the locally enhanced fields excited at the gold gratings, finally resulting in a strong and deep absorption band at resonance. Therefore, the proposed structure could potentially open a new possibility of the enhanced LSPR detection for monitoring biomolecular interactions of low molecular weights.
authors.affiliation: School of Electrical Engineering and Computer Science, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Seong Min
authors.initials: SM
authors.lastname: Jang
authors.forename: Donghyun
authors.initials: D
authors.lastname: Kim
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Kyung Min
authors.initials: KM
authors.lastname: Byun
authors.forename: Sung June
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry; D009716:Numerical Analysis, Computer-Assisted; D012822:Silicon Dioxide / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D006046:Gold; D012822:Silicon Dioxide