Sensing devices and techniques using 3-D arrays based on surface plasmon excitations
Techniques, apparatus, material and systems are described for implementing a three-dimensional composite mushroom-like metallodielectric nanostructure. In one aspect, a surface plasmon based sensing device includes a substrate and a layer of an anti-reflective coating over the substrate. The surface Plasmon based sensing device includes a dielectric material on the anti-reflective coating shaped to form a 2-dimensional array of nanoholes spaced from one another. Also, the surface Plasmon based sensing device includes a layer of a metallic film formed on the 2-dimensional array of nanoholes to include openings over the nanoholes, respectively, wherein the sensing device is structured to support both propagating surface plasmon polariton (SPP) waves and localized surface plasmon resonant (LSPR) modes.
1. A surface plasmon based sensing device, comprising:
a substrate;
a layer of an anti-reflective coating formed over the substrate;
a dielectric layer formed on the anti-reflective coating, wherein the dielectric layer includes an array of nanoholes formed in the dielectric layer and spaced from one another; and
a metal layer formed on the dielectric layer, wherein the metal layer includes openings over the array of nanoholes in the dielectric layer, wherein each opening is over a respective nanohole in the array of nanoholes, thereby forming a 3-dimensional composite metallodielectric nanoresonant array,
wherein the 3-D composite metallodielectric nanoresonant array is structured to excite both propagating surface plasmon polariton (SPP) waves and localized surface plasmon resonant (LSPR) modes when a light beam impinges on the 3-D composite metallodielectric nanoresonant array, and wherein the excited SPP and LSPR provide surface plasmon resonance (SPR) sensing.
2. The surface Plasmon based sensing device of claim 1 , wherein the metal layer comprises a layer of gold formed to control a size of the openings.