Chemical and biological sensing using metallic particles in amplifying and absorbing media
A film for surface enhanced raman scattering may be utilized for chemical and biological sensing. The film includes a polymeric layer, and a metallic nanoparticle having a cross-section, the metallic nanoparticle being embedded in the polymeric layer. The polymeric layer has a thickness less than a largest straight line through the cross-section of said metallic nanoparticle. The polymeric layer is selected from a group of absorbing media and amplifying media, and the metallic nanoparticle may be gold. The metallic nanoparticle may also be a shape selected from a group of spheroids and rods.
1. A film for surface enhanced Raman scattering, comprising:
a layer including a gain medium; and
a nanoparticle capable of polariton resonance, the nanoparticle having a cross-section and being embedded in the layer;
wherein the layer has a thickness less than a largest straight line through the cross-section of the nanoparticle.
2. The film of claim 1 wherein the nanoparticle has a shape selected from a group of spheroids and rods.
3. The film of claim 1 wherein the polariton resonance is plasmon-polariton resonance.
4. The film of claim 1 wherein the polariton resonance is phonon-polariton resonance.
5. The film of claim 1 further comprising a substrate on which the layer is disposed.
6. The film of claim 5 wherein the substrate is transparent.
7. The film of claim 5 wherein the substrate is absorbing.
8. A film for surface enhanced Raman scattering, comprising:
a first layer;
a metallic nanoparticle having a cross-section and being embedded in the first layer; and
a thin film layer disposed on the first layer for attachment of moieties;
wherein the first layer has a thickness less than a largest straight line through the cross-section of the metallic nanoparticle.
9. The film of claim 8 wherein the first layer is selected from a group of absorbing media and amplifying media.
10. The film of claim 8 wherein the metallic nanoparticle has a shape selected from a group of spheroids and rods.
11. The film of claim 8 wherein the thin film layer comprises functionalized SiO 2 .
12. The film of claim 8 wherein the thin film layer has a thickness less than 5 nm.
13. The film of claim 8 further comprising a substrate on which the first layer is disposed.
14. The film of claim 13 wherein the substrate is transparent.
15. The film of claim 13 wherein the substrate is absorbing.