Plasmonic petal-shaped beam for microscopic phase-sensitive SPR biosensor with ultrahigh sensitivity
Wang, Rong (EEE)
Date of Issue2013
School of Electrical and Electronic Engineering
Differential phase measurement between radially polarized (RP) and azimuthally polarized (AP) beams is an important technique in microscopic surface plasmon resonance (SPR) biosensors as reported in our earlier works [Opt. Lett. 37, 2091 (2012); Appl. Phys. Lett. 102, 011114 (2013)]. However, such a technique suffers complex beam splitting, detection, and data processing procedures for RP and AP beams which may lower the accuracy of phase measurement. In this Letter, a novel plasmonic petal-shaped vector beam is proposed instead of RP and AP beams, greatly simplifying the sensor system and enabling single measurement in differential interferometry. Moreover, an improved ultrahigh sensitivity on the order of 10−7 refractive index units (RIUs) is experimentally verified in the proposed system.
DRNTU::Engineering::Electrical and electronic engineering::Optics, optoelectronics, photonics
© 2013 Optical Society of America. This paper was published in Optics Letters and is made available as an electronic reprint (preprint) with permission of Optical Society of America. The paper can be found at the following official DOI: [http://dx.doi.org/10.1364/OL.38.004770]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.