Synopsis: Superconductor optics

In the domain of unusual optical properties, layered superconductors could be viable materials with a negative index of refraction.
Synopsis figure
V. Golick et al., Phys. Rev. Lett. (2010)

Materials with a negative index of refraction bend and guide a beam of light in unconventional ways—an effect that could be exploited to make perfect lenses. The search for candidate negative-index materials has identified multilayers of high-temperature superconductors as a possibility. Because these materials are anisotropic, the sign of the electrical permittivity (or, more specifically, elements of the permittivity tensor) can change over a certain frequency range, which opens the possibility for negative-index refraction.

Writing in Physical Review Letters, Vladislav Golick and colleagues at Kharkov University in the Ukraine, in collaboration with scientists in the Ukraine, Russia, Japan, and the US, calculate dispersion curves for so-called “surface Josephson-plasma waves” in layered superconductors. They find a branch of these waves above the Josephson plasma frequency, displaying abnormal surface mode behavior. They also identify a window of THz frequencies (above the plasma frequency) where the permittivities switch signs to produce negative-index refraction. At higher frequencies, their model predicts that light incident through a high-index, transparent medium would be completely refracted (no reflection) inside the layered superconductor.

When the superconductor-layer width is below the free path of the surface waves, the refracted waves could be emitted from the edge of the superconductor in the form of a highly collimated beam. With a magnetic field applied parallel to the layers, it should be possible to modulate this channeling effect to make fast switching shutters and mirrors for guiding light. –Saad E. Hebboul


More Features »


More Announcements »

Subject Areas


Previous Synopsis

Biological Physics

Hidden epidemic

Read More »

Next Synopsis

Related Articles

Synopsis: Atoms Feel New Force
Atomic and Molecular Physics

Synopsis: Atoms Feel New Force

Laser light can stretch and squeeze a whole cloud of atoms with a collective force. Read More »

Focus: Modeling Imperfections Boosts Microscope Precision

Focus: Modeling Imperfections Boosts Microscope Precision

A theoretical model of light spreading and scattering improves precision of position and size measurements made with an optical microscope by as much as 100 times. Read More »

Synopsis: Attosecond X-Ray Flashes

Synopsis: Attosecond X-Ray Flashes

X-ray free-electron lasers have been used to generate single spikes of hard x rays that are only 200 attoseconds long. Read More »

More Articles