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Title: Cobalt stabilization of silver extraordinary optical transmission sensing platforms

In this study, plasmon-mediated extraordinary optical transmission (EOT) is finding increased interest for biosensing applications. While Ag nanostructures are capable of the highest plasmonic quality factor of all metals, the performance reliability of pure Ag EOT devices is limited by degradation through environmental interactions. Here we show that EOT devices consisting of nanostructured hole arrays in Ag/Co bilayers show comparable transmission with that of identical hole arrays in Agthin films as well as enhanced reliability measured by the rate of resonance peak redshift and broadening with time. The Ag/Co EOT devices showed 2.6× and 1.9× smaller red shift in short timescales (20 days) and after 100 days, respectively, while they showed a 1.7× steady-state decrease in rate of bandwidth broadening. This improvement is likely due to the Co metal stabilizing the Agfilm from morphological changes by reducing its propensity to diffuse or dewet on the underlying substrate. The improved reliability of Ag/Co bilayer EOT devices could enable the use of their superior plasmonic properties for optical detection of trace chemicals.
 [1] ;  [2] ;  [3] ;  [3] ;  [1] ;  [1]
  1. Univ. of Tennessee, Knoxville, TN (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Vanderbilt Univ., Nashville, TN (United States)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Applied Physics Letters
Additional Journal Information:
Journal Volume: 108; Journal Issue: 4; Journal ID: ISSN 0003-6951
American Institute of Physics (AIP)
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
Country of Publication:
United States
77 NANOSCIENCE AND NANOTECHNOLOGY; silver; red shift; electron beam deposition; gold; metallic thin films
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1235803