Chiral plasmonics

Chiral Plasmonics Three-dimensional Light-Matter Interaction... 

Kuzyk, A., Schreiber, R., Fan, Z., Pardatscher, G., RoUer, E.M., Hogele, A., Simmel, F.C., Govorov, A.O., Liedl,T, 2012. DNA-based self-assembly of chiral plasmonic nanostructures with tailored optical response. Nature 483 (7389), 311-314. 

Based on the stereoselectivity of immunoglobulins, a new chiral sensor for the detection of low-molecular-weight analytes was developed. Using surface plasmon resonance detection, enantiomers of free, underivatized a-amino acids can be monitored in a competitive assay by their interaction with antibodies specific for the chiral center of this class of substances. The sensitivity to the minor enantiomer in non-racemic mixtiues exceeds cunently available methods therefore, such immuuoseusors can readily detect traces of enantiomeric impurities and are attractive for a range of applications in science and industry. 

In the chiral gratings, the resonance features associated with surface plasmons at the metal-air interface is nearly independent on the incident angle,... 

Non-chiral nanoparticles were also of interest for sensing of optical activity through the enhancement of the chirality of molecules in the presence of the plasmonic field at the edge of, for example nanocubes or gold structures on surfaces. ... 

In another work, silica nano helices have been prepared from the organic self-assemblies of -tartrate amphiphiles by sol-gel transcription. Then this chiral nanostructures were functionalized with (3-aminopropyl)-trietho)y-silane (APTES) or (3-mercaptopropyl)triethoxysilane (MPTES) and decorated with gold nanoparticles of various diameters (1-15 nm) resulting in nanohelix hybrid structures (Fig. 25). ° It was found that the surface plasmon resonance intensity of these nanohybrid systems increased with gold particle size. Gold nanoparticles of 10-14 nm diameter have clearly showed a surface enhanced effect on Raman spectroscopy. This sj tem is a unique example of the 3D hybrid network that could be used as ultrasensitive chemical and biological sensors for detection of molecules of interest in liquids by accumulation under flow. 

Haase W, Podgomov F, Matsuhisa Y, Ozaki M (2008) Lasing in dye-doped chiral liquid crystals influence of defect modes. In Wehrspohn RB, Kitzerow H-S, Busch K (eds) Nanophotonic materials photonic crystals, plasmonics and metamaterials. Wiley-VCH, Weinheim, p 239... 

Chiro-optical properties. The optical properties specific of chiral molecules (optical rotation, circular dichroism, Raman optical activity (ROA)) may also be enhanced by the interaction with plasmons. This very interesting field is much less developed than others, although theoretical contributions have already been published (e.g. for surface-enhanced Raman optical activity, SEROA) [48,49]. 

Abdulrahman, N.A., Fan, Z.,Tonooka,T., Kelly, S.M., Gadegaard,N., Hendry, E., Govorov, A.O., Kadodwala, M., 2012. Induced chirahty through electromagnetic coupling between chiral molecular layers and plasmonic nanostructures. Nano Lett. 12 (2), 977—983. 

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