Long-range surface plasmon Y-junctions for referenced biosensing

Abstract

Long-range surface plasmon Y-junctions are demonstrated as sensors for the detection of bulk refractive index changes in solution and for protein binding. Using a fully-cladded Au stripe waveguide as a reference channel, common drift and noise in the system can be eliminated, relaxing the need for precise optical alignments. The performance of the structure is discussed theoretically, then bulk sensing is carried out experimentally with five solutions of different refractive indices, and protein sensing is demonstrated through physisorption of bovine serum albumin on a carboxyl-terminated Au stripe. The Y-junction biosensor demonstrated a very good ability to perform drift and noise suppression for fast and accurate biosensing.

Surface plasmon enhanced photodetectors based on internal photoemission

“…1,2 SPPs are promising for several applications including optical data center interconnects, [3][4][5][6] solar cells, [7][8][9] and bio(chemical) sensors. [10][11][12][13][14][15] In such applications, surface plasmons (SPs) are excited by light and supported on a variety of metal and dielectric structures including planar arrangements of metal and dielectric films, 16 metal gratings (or hole arrays), 5,17,18 a prism, 19 a metal edge, 20,21 and metal nanoparticles such as islands, spheres, rods, 22,23 or nanoantennas. 24,25 The ability of SPs to resonate or propagate on metallic structures enables them to have interesting and useful attributes such as high bulk and surface sensitivities, subwavelength confinement and energy asymptotes in dispersion curves which have led to many different applications.…”

Focus Issue on surface plasmon photonics introduction

“…With this approach, they demonstrated biotinylated surface capture of neutravidin concentrations as low as 10 nM with a 5.5 nM limit of detection. Another biosensor was reported by Wong et al [6]. This device is based on long-range surface plasmons in Y-junctions.…”

Hybrid fiber resonator employing LRSPP waveguide coupler for gyroscope

“…Long-range surface plasmon polaritons (LRSPP) waveguides is a new research hotspot of integrated optics121314. This waveguide consists of nanometer-thin metal strips embedded in homogeneous dielectric environment.…”

“…LRSPPs show good mode-matching to conventional optical fibers18, as well as simultaneous guiding of optical and electrical signals1920. These advantages render LRSPP waveguides an outstanding platform for specialized applications in high-precision optics132122232425.…”