Open AccessOptimization of angularly resolved Bloch surface wave biosensors
Author(s) -
Riccardo Rizzo,
Norbert Danz,
Francesco Michelotti,
Emmanuel Maillart,
Aleksei Anopchenko,
Christoph Wächter
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.023202
Subject(s) - figure of merit , optics , stack (abstract data type) , surface plasmon resonance , materials science , resonance (particle physics) , thin film , surface wave , surface plasmon , physics , plasmon , computer science , nanotechnology , particle physics , nanoparticle , programming language
Bloch surface wave (BSW) sensors to be used in biochemical analytics are discussed in angularly resolved detection mode and are compared to surface plasmon resonance (SPR) sensors. BSW supported at the surface of a dielectric thin film stack feature many degrees of design freedom that enable tuning of resonance properties. In order to obtain a figure of merit for such optimization, the measurement uncertainty depending on resonance width and depth is deduced from different numerical models. This yields a limit of detection which depends on the sensor's free measurement range and which is compared to a figure of merit derived previously. Stack design is illustrated for a BSW supporting thin film stack and is compared to the performance of a gold thin film for SPR sensing. Maximum sensitivity is obtained for a variety of stacks with the resonance positioned slightly above the TIR critical angle. Very narrow resonance widths of BSW sensors require sufficient sampling but are also associated with long surface wave propagation lengths as the limiting parameter for the performance of this kind of sensors.