Link to the paper: http://www.nature.com/ncomms/2015/150922/ncomms9433/pdf/ncom...
This is an excellent result. It could also provide an interest boost to solar in terms of $/watt by focusing more light into a small area. Fun times.
This is an excellent result. It could also provide an interest boost to solar in terms of $/watt by focusing more light into a small area. Fun times.
I can't find a single use of this for solar based on the specifications of the lens in the paper. Also photovoltaic really doesn't need focusing it doesn't give you anything because eventually the amount of power you get per surface area is the same so it doesn't matter if you cover a 50 sq/m area with a lens and focus it on a 5 sq/m cell or have a 50 sq/m cell to begin with, also considering that photovoltaic cell efficiency drops with temperature you really don't want to focus any light on them as it will tank your power production.
Thermal solar does need focusing but mirrors will actually work better than this for that application as well because you need to reflect the light to a central location anyhow an a collection mirror does both at the same time.
https://en.wikipedia.org/wiki/Solar_thermal_energy
For photovoltaics you do not want to focus the light for many reasons the cell has a cap per surface area that it can produce, you don't want voltage spikes across the subcells (if it exceeds the overall limits of the cell it will damage it), it wears out the cell, and the cell efficiency drops as the temperature increases.
You're correct that at some point you get undesirable transients, or you just melt your cell. I do that by accident more often than I'd like, by shining infrared lasers at a photo diodes while forgetting that I've left a microscope objective in front. Expensive mistakes.
Now re: the article, if you ask me the really interesting thing here isn't being able to focus light to really small areas per se, but that they've broken the diffraction limit. This means you can form an image of an object that is smaller than a half-wavelength of light. For e.g. red light, that means you can take a picture, an optical picture, of something like, say, a mosfet on a chip. Or a virus. That's quite something.
I'll note however that I could foresee (read: speculate) a scenario where having such a tiny focus, like the solar cell scenario, could invoke a quantum mechanical effect in some special material whereby the light coupling becomes much greater, thus increasing efficiency or something. But that's just science fiction as far as I know.
PS: Sorry if this is patronizing. I know nothing about my audience ;-)
I know pretty much nothing about it besides the fact that it exists, though.