Ultrastable embedded surface plasmon confocal interferometry

Pechprasarn, Suejit; Zhang, Bei; Albutt, Darren; Zhang, Jing; Somekh, Michael

Abstract

As disease diagnosis becomes more sophisticated, there is a requirement to measure small numbers of molecules attached to, for instance, an antibody. This requires a sensor capable not only of high sensitivity but also the ability to make measurements over a highly localized region. In previous publications, we have shown how a modified confocal microscope allows one to make localized surface plasmon (SP) measurements on a scale far smaller than the surface plasmon propagation distance. The present implementation presents a new ultrastable interferometer system, which greatly improves the noise performance. Hitherto, we have used the central part of the back focal plane to form a reference beam with the reradiated surface plasmons. In the current system, we block the central part and use the spatial light modulator to deflect s-polarized light into the pinhole to form an interference signal with the surface plasmons, thus creating an ultrastable interferometer formed with two beams incident at very similar angles. We demonstrate the superior noise performance of the system in hostile environments and examine further adaptations of the system to further enhance noise performance.

Citation

Pechprasarn, S., Zhang, B., Albutt, D., Zhang, J., & Somekh, M. (2014). Ultrastable embedded surface plasmon confocal interferometry. Light: Science and Applications, 3(7), Article e187. https://doi.org/10.1038/lsa.2014.68

• Journal Article Type: Article
• Acceptance Date: Apr 12, 2014
• Online Publication Date: Jul 4, 2014
• Publication Date: 2014-07
• Deposit Date: Oct 22, 2020
• Publicly Available Date: Oct 22, 2020
• Journal: Light: Science & Applications
• Print ISSN: 2047-7538
• Publisher: Springer Nature [academic journals on nature.com]
• Peer Reviewed: Peer Reviewed
• Volume: 3
• Issue: 7
• Article Number: e187
• DOI: https://doi.org/10.1038/lsa.2014.68
• Public URL: https://nottingham-repository.worktribe.com/output/4983728
• Publisher URL: https://www.nature.com/articles/lsa201468
• Additional Information: Received: 28 November 2013; Revised: 9 April 2014; Accepted: 12 April 2014; First Online: 4 July 2014