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"Plasmon rulers can be used to determine nanoscale distances within chemical or biological species. They are based on the spectral shift of the scattering spectrum when two plasmonic nanoparticles approach one another.... We demonstrated a three-dimensional plasmon ruler that is based on coupled plasmonic oligomers in combination with high-resolution plasmon spectroscopy. This enables retrieval of the complete spatial configuration of complex macromolecular and biological processes as well as their dynamic evolution."

The first complete theory of how plasmons produce "hot carriers" has been developed by researchers in the US. The new model could help make this process of producing carriers more efficient, which would be good news for enhancing solar-energy conversion in photovoltaic devices.

I did not read the paper but what is further down written in the article, does not give much hope that this actually gives much more insight than what we had nor that it could be used in any way to improve current PV cells soon: e.g. "To fully exploit these carriers for such applications, researchers need to understand the physical processes behind plasmon-induced hot-carrier generation. Nordlander's team has now developed a simple model that describes how plasmons produce hot carriers in spherical silver nanoparticles and nanoshells. The model describes the conduction electrons in the metal as free particles and then analyses how plasmons excite hot carriers using Fermi's golden rule - a way to calculate how a quantum system transitions from one state into another following a perturbation. The model allows the researchers to calculate how many hot carriers are produced as a function of the light frequency used to excite the metal, as well as the rate at which they are produced. The spectral profile obtained is, to all intents and purposes, the "plasmonic spectrum" of the material. Particle size and hot-carrier lifetimes "Our analyses reveal that particle size and hot-carrier lifetimes are central for determining both the production rate and the energies of the hot carriers," says Nordlander. "Larger particles and shorter lifetimes produce more carriers with lower energies and smaller particles produce fewer carriers, but with higher energies."

Again some plasmonic metamaterial...

Spectral dispersion of light on a finite-size surface plasmon polaritonic (SPP) crystal has been studied. The angular wavelength separation of one or more orders of magnitude higher than in other state-of-the-art wavelength-splitting devices available to

Known technically as a surface plasmon polariton (SPP) wave, the effect will allow the nano-antennas to operate at the low end of the terahertz frequency range, between 0.1 and 10 terahertz - instead of at 150 terahertz With this antenna, we can cut the frequency by two orders of magnitude and cut the power needs by four orders of magnitude," said Jornet. "Using this antenna, we believe the energy-harvesting techniques developed by Dr. Wang would give us enough power to create a communications link between nanomachines." As always, graphene seems to be the answer to anything, but steady progress is being made although one needs to find out first an easy method of generating high quality graphene layers (btw that is also one of the reasons to do the supercapacitor study...)

Well plasmonics is also the solution to everything it seems...

See Also: Matter & Energy Nanotechnology Optics Physics Materials Science Graphene Organic Chemistry Reference White gold Electromagnetic radiation Nanomedicine Nanoparticle Any use for the smell project? "We have demonstrated resonant antenna-enhanced single-particle hydrogen sensing in the visible region and presented a fabrication approach to the positioning of a single palladium nanoparticle in the nanofocus of a gold nanoantenna,"

Bio-inspired assembly of fluorescent molecules boosts the fluorescence output.

Nice read! It is actually part of the Ariadna PETE study of one of the teams. You can supervise if you want :)

Basis for after next generation processors?

"We have made optical systems at the microscopic scale that amplify light and produce ultra-narrowband spectral output," explained J. Gary Eden, a professor of electrical and computer engineering (ECE) at Illinois. "These new optical amplifiers are well-suited for routing optical power on a chip containing both electronic and optical components.

Metasurfaces have been made, but the problem is that they usually are static and for quantum optic applications the question is how to make a rapidly configurable metasurface. for this Harvard has initiated a multidisciplinary team that involves theoretical physics, metamaterials, nanophotonic circuitry, quantum devices, plasmonics, nanofabrication, and computational modeling

Reading "wavefront engineering" in the title I thought it had to do with wave manipulation in the sea. Nothing to do though. As I read further in this article, Harvard thrives in forming multidisciplinarity groups. Their practice is to call the best team in each expertise they need to merge. Not one researcher from each discipline, but teams of experienced professors and a series of graduate students. Maybe we could discuss it in the retreat!

A new paper related to our old Ariadna on microstructured radiators.

This is actually a very nice paper in my view .... José, have a look at it!! "This study demonstrates that appropriately designed metallo-dielectric systems can serve as compact, highly directive and ultra radiative antennas. Let us emphasize that contrary to fully metallic antennas, the high directivity of this antenna does not result from a plasmonic effect, and that it is efficient over a wide range of frequencies. In consequence, the high directivity does compromise the high radiative decay rate enhancement offered by two coupled metallic particles and it is possible to exploit whispering gallery modes to further enhance the radiative decay rates. This work paves the way towards the design of compact, simple and highly efficient optical antennas."

I forwarded the link to my experimental colleagues and here is the comment from Sergei (the master himself:) "this is what Igor has been doing - an array of plasmonic nanocables. This basically works as a wire-medium slab. All their epsilon and mu are rubbish." * If Sergei is as strict as in this comment, then it IS rubbish. He's not one of the notorious complainer (as e.g. myself.) * Please DO NOT FORWARD this to anybody else, Sergei's comment is NOT FOR PUBLIC USE!

UPDATE: I had a short chat with Sergei and Pekka, Sergei noticed that there is an increasing number of papers on metamaterials, especially in Nature and Science, which are simply wrong, this one being an example. * The idea is based on a very well known effect of wired media. What appears to be interesting about this paper is that they manage to make an optical analogue with aparently low losses. This could be interesting. * The whole interpretation as NIM, "wrong" refraction etc. is total nonsense.

wow, good to know ! But for the privacy you should be aware that this is a public group, so anyone has access to our comments i think !

graphene for solar cells ... who wants to have a closer look at it?

Why not but I'm not sure I have the competences/background to do much...