Influence of the Evanescent Field Decay Length on the Sensitivity of Plasmonic Nanodisks and Nanoholes
Artikel i vetenskaplig tidskrift, 2015

We evaluate and compare the sensitivity of gold nanodisks on silica substrates and nanoholes made in silica-supported gold films, two of the most common sensor structures used in plasmonic biosensing. An alumina overcoat was applied by atomic layer deposition (ALD) to precisely control the interfacial refractive index and determine the evanescent plasmonic field decay length. The results are in good agreement with analytical models and biomolecular binding experiments for the two substrates. We found that nanodisks outperform nanoholes for thin dielectric coatings ( similar to 20 nm). The optimum nanoplasmonic transducer element for a given biorecognition reaction can be chosen based on experimentally determined bulk sensitivities/noise levels and theoretically estimated evanescent field decay lengths.

atomic layer deposition

nanodisk

surface plasmon resonance

biosensing

nanohole

plasmonics

Författare

Francesco Mazzotta

Chalmers, Teknisk fysik, Biologisk fysik

T. W. Johnson

University of Minnesota System

Andreas Dahlin

Chalmers, Teknisk fysik, Bionanofotonik

J. Shaver

University of Minnesota System

S. H. Oh

University of Minnesota System

Fredrik Höök

Chalmers, Teknisk fysik, Biologisk fysik

ACS Photonics

2330-4022 (eISSN)

Vol. 2 256-262

Ämneskategorier

Atom- och molekylfysik och optik

Nanoteknik

DOI

10.1021/ph500360d