Nonequilibrium superconductivity in alkali fullerides
The resonant excitation of the K3C60 fulleride superconductor led to the observation of a transient superconducting-like phase at unprecedented temperatures, far beyond equilibrium Tc
M. Mitrano et al., Nature 530, 461 (2016)
Superconductors have long been confined to a limited number of applications, with their highest transition temperature being 200 K (at high pressure conditions), and are at present mainly used in magnets for nuclear magnetic resonance tomographs, fusion devices and particle accelerators. One fundamental problem is finding a way to raise the critical temperature up to ambient condictions and develop cheap, scalable superconductor-based solutions for lossless energy distribution. In the present experiment K3C60 samples were excited with femtosecond midinfrared light pulses tuned to match the characteristic C60 intramolecular vibrational frequencies. |
Strikingly, for a wide range of temperatures up to at least 100 K (5 time Tc), the light-induced phase exhibited the same characteristic hallmarks of the equilibrium superconducting transition. The discovery may lead to a more comprehensive understanding of the phenomenon of light-induced superconductivity, and potentially give hints in the direction of synthesizing novel superconductors with highercritical temperatures.
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Ultima modifica il Venerdì, 10 Febbraio 2017 12:27