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Physicists Close in on 'Superlens'
An anonymous reader writes "In Oregon, physicists have developed a material for creating a real superlens that in theory could attain a one-nanometer visual resolution. The idea is to use exotic materials to create "negative" refraction of light, which literally means steering it in the opposite direction of that found in the natural world."
In a conventional lens, light gets bent
Poor light. Why is everyone so mean to it? It just wants to be loved, but everyone wants it to get bent.
Could these be set up like a traditional light microscope to make a cheaper atom scanning microscope than the electron microscope? This could open an entirely new door in the study of atomic particles.
I'm not sure about the resolution of the previous "negative refractive" lenses, but these things have been around for a few years. Pendry (I think) was one of the first to come up with the split-ring "metamaterial" and show that it can work, but the concept for these things has been around since Veselago came up with them, oh, about 40 years ago. People (including my advisor) have recently been proposing or demonstrating "negative refraction" acoustical materiaals, too. As far as I can make out from the summary, the OSU work is notable because this lens might work with optical frequencies, rather than in the radio and microwave regime, as previous optical metamaterials had to do.
Incidentally, people will find better information by searching for "left-handed" and "metamaterial" rather than "negative index" on the various sites.
I thought you can get negative refraction, when an electromagnetic wave passes through a "Metamaterial" i.e. One with Negative Permittivity and Permeability.
(for instnace, in a dispersive plasma cloud)
Sigs are for the weak.
Anybody who has ever done a university course on optics and so has come across phenomena like double refraction, which is truly weird the first time you see it, will know that there are plenty of strange things in optics. But that doesn't make them unnatural.
Pining for the fjords
I always thought that zone plates ("lenses" that use diffraction instead of refraction) give a higher degree of accuracy a lower wavelengths. Zone plates are often used where a traditional lens is opaque to certain wavelengths outside of the visible spectrum.
Being a grad student in these kind of things (optics) I just want to clarify that these super-"lenses" do not behave at all like normal lenses. Most importantly, it is impossible to obtain magnification, the image will always be exactly the same size as the object. So it's not really fair to think about them as "lenses".
A very similar thing is dispersion compensation in fiber-optical communications where the dispersion of one fiber is compensated in another with dispersion of opposite sign. This way, a signal can go through the two fibers without being distorted by the chromatic dispersion. Dispersion and diffraction (i.e. free space light propagation)are mathematically virtually the same thing, and the negative-index material is equivalent to having a fiber with dispersion of the opposite sign. So perhaps it's more right to think about the super.lenses as "diffraction-compensators"?
I mean, how do you get 1nm visual resolution, when the wavelength of visual light ranges from 400-800 nm?
Finally there'll be a way to read all the fine print in service contracts!
As a Lisp programmer, I chuckle at the artificial distinction between light, lenses, and refraction.
Your hybrid is not saving the environment. Its purpose is to make you feel good about buying something.
The idea is to use exotic materials to create "negative" refraction of light, which literally means steering it in the opposite direction of that found in the natural world.
I have one of those! I call it a *hand quotes* mirror *hand quotes*.
The actual paper (PDF file): http://www.physics.oregonstate.edu/~vpodolsk/repri nts.pdf/resolut.apl2005.pdf
You can find more information about this research at Podolskiy's web page. It looks like the web site has some good information, including Java applets showing how a superlens should work. Incidently, I am an undergrad physics student at OSU and I talked to Poldolskiy about doing some research for him last summer, but it didn't work out. It's nice to see he got something published on this though - he was explaining it to me last year but I can't remember much of it now.
It should also be noted that these negative index materials rely on resonant behaviour, and are consequently highly dispersive.