Enhancement of side‐coupled surface plasmon resonance sensitivity by application of polymethylmethacrylate thin polymer films. (22nd April 2020)

• Record Type: Journal Article
• Authors: Amjad, Saima; Swargiary, Kankan; Somarapalli, Manjunath; Bora, Tanujjal; Hornyak, Gabor L.; Mohammed, Waleed S.
• Is Part Of: Micro & nano letters. Volume 15:Number 5(2020)
• Page Start: 327
• Page End: 332
• Publication Date: 2020-04-22
• Subjects: polymer films -- surface plasmon resonance -- gold -- refractive index -- thin film sensors -- chemical sensors -- water; SPR incident angle -- effective refractive index -- sensing region -- device sensitivity -- dynamic detection range -- Au -- first‐order approximations -- gold layer thickness -- film materials -- excitation system -- theoretical investigation -- polymethylmethacrylate thin polymer films -- side‐coupled surface plasmon resonance sensitivity -- theoretical expectations -- PMMA layer -- untreated surfaces -- water‐chloroform mixtures -- gold surfaces -- PMMA thin films -- measured SPR responses -- SPR chips -- characterisation scheme; Nanotechnology -- Periodicals; Nanostructures -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1049/mnl.2019.0656
• Languages: English
• ISSNs: 1750-0443

Abstract

Abstract : Here the theoretical and experimental investigation for enhancing surface plasmon resonance (SPR) sensitivity in a side‐coupled excitation system by the application of polymethylmethacrylate (PMMA) polymer thin films is presented. Proper selection of film materials, gold layer thicknesses d Au and SPR incident angle ( θ SPR ) resulted in the increased effective refractive index of the sensing region, and hence of the device sensitivity, and the dynamic detection range. This work demonstrates, by first‐order approximations, a characterisation scheme of SPR chips with unknown gold layer thickness d Au and uncertainty in SPR incident angle. The scheme utilised fitting theoretical calculations to measured SPR responses while varying d Au and θ SPR in equations. Device sensitivity nearly doubled following application of thin PMMA thin films on gold surfaces when sensing water‐chloroform mixtures as opposed to untreated surfaces that lacked a PMMA layer. The proposed work demonstrates a facilitative balance between theoretical expectations and experimental data to develop sensors for future applications.