Miniaturized, High Resolution Plasmonic Sensors

Ibrahim Abdulhalim, Electrooptics and Photonics Engineering, BEN GURION UNIV OF THE NEGEV, Beer Sheva, Israel (ABDULHLM@BGU.AC.IL)

The enhanced local optical fields near metal surfaces when surface plasmons are excited allows higher sensitivity sensing, specificity by utilizing the nanoscale optical penetration depth of the evanescent wave, reproducibility and durability due to the use of gold as standard durable sensing surface.  Enhancing the functionality of plasmonic sensors can be done also by combining them with dielectric surfaces such as using metal-insulator-metal or insulator-metal-insulator structures.  All these features together with the ease of plasmon excitation allow for building miniaturized, high resolution plasmonic sensors.  In this lecture I will review our recent works which demonstrate this as a sensing device with some specific sensing applications including the following:

1. Buildup of a low cost SPR sensing device (H5-SPR) weighing less than 1kg with dimensions 22x5x12cm, capable of detecting refractive index changes down to 1RU.


2. Integration of the above-mentioned device with magnetic field capability in which magnetic nano particles (MNP) can be dragged to the plasmonic surface on demand. Detection of one MNP is demonstrated, meaning one should be able to detect one molecule attached to the MNP.


3. Ability to tune the penetration depth so the substrate becomes suitable also for bacteria and even biofilm monitoring using an insulator-metal-insulator structure that performs also as a self-referenced sensor.


4. Ultrahigh enhancement of the local optical fields by exciting the localized plasmons with extended ones demonstrated using the prism coupling configuration, the grating coupling and recently without coupling medium using 3D network of hot spots generated by micro-porous Si substrate coated with 200nm gold. SERS enhancement factors of the order of 10⁷-10¹⁰ are demonstrated on variety of analytes including bacteria, picric acid with nM resolution limited by the well-known problem of variability over the SERS surface. Methods how to minimize the variability will be discussed.

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Short Biography of Presenting Author

Prof. Ibrahim Abdulhalim: is a professor in the Department of Electrooptics and Photonics Engineering at Ben Gurion University.  He has worked in research and development in variety of academic institutions and industrial companies such as: the Optoelectronic Computing Systems Center in the University of Colorado at Boulder, USA, the Optoelectronics Research Center of Southampton University, England, the Thin Films Center of the University of Western Scotland, KLA-Tencor and Nova measuring instruments, and in GWS-Photonics.  Since October 2005 he joined the Department of Electrooptic Engineering at Ben Gurion University and acted as the department head between 2006-2014.  His current research activities involve liquid crystal devices for photonic applications, nanophotonic and plasmonic structures for biosensing, optical imaging techniques for biomedical and metrology applications such as spectropolarimetric imaging and full field optical coherence tomography.  Prof. Abdulhalim has published over 220 journal articles, 70 conference proceedings papers, 11 book chapters, coauthored one book titled: Integrated Nanophotonic Devices (Micro and Nano Technologies), co-edited a book titled: Signal amplification in optical biosensing, and has 22 granted patents.  He became a fellow of the Institute of Physics, UK in 2004, SPIE fellow in 2010 and senior member of Optica in 2016.  He is an associate editor of the SPIE Journal of NanoPhotonics, and the Journals of Sensors, and Biosensors.  In 2014 he founded the company Photonicsys, specialized in optical and photonic devices for biosensing, and in 2019 a company named Photoliqsys, specialized in unique liquid crystal devices and applications.