Enhancement of side-coupled surface plasmon resonance sensitivity by application of polymethylmethacrylate thin polymer films

Micro & nano letters

article

Saima Amjad¹  Kankan Swargiary³  Manjunath Somarapalli³  Tanujjal Bora¹  Gabor L. Hornyak¹  Waleed S. Mohammed³ 

[1] Center of Excellence in Nanotechnology, Asian Institute of Technology;Industrial Systems Engineering, School of Engineering & Technology, Asian Institute of Technology;Center of Research in Optoelectronics, Communication and Computational Systems (BU-CROCCS), School of Engineering, Bangkok University

关键词: 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;   

DOI  :  10.1049/mnl.2019.0656

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

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.

【 授权许可】

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