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Energy gap in superconducting fullerides: optical and tunneling studies

Daniel Koller·Michael C. Martin·Laszlo Mihaly·Gyorgy Mihaly·Gabor Oszlanyi·Gabriel Baumgartner·Laszlo Forro
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Abstract

Tunneling and optical transmission studies have been performed on superconducting samples of Rb3C60. At temperatures much below the superconducting transition temperature Tc the energy gap is 2 Delta=5.2 +- 0.2meV, corresponding to 2 Delta/kB Tc = 4.2. The low temperature density of states, and the temperature dependence of the optical conductivity resembles the BCS behavior, although there is an enhanced ``normal state" contribution. The results indicate that this fulleride material is an s-wave superconductor, but the superconductivity cannot be described in the weak coupling limit.

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Daniel Koller, Michael C. Martin, Laszlo Mihaly, Gyorgy Mihaly, Gabor Oszlanyi, Gabriel Baumgartner, Laszlo Forro. 1996-09-27. Energy gap in superconducting fullerides: optical and tunneling studies. https://doi.org/10.1103/physrevlett.77.4082

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