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Critical Temperature T_c versus Charging Energy E_c in MgB2 and C60/CHBr3

Chikao Kawabata·Nobuhiko Hayashi·Fumihisa Ono
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Abstract

The boride compounds MB_x related to the magnesium-boron stacking layered material MgB2 are discussed in terms of the B-B layers in the borides analogous to the Cu-O ones in the cuprates. We propose a possibility of superconducting materials which exhibit higher critical temperature T_c than 39 K of MgB2. We point out a role of interstitial ionic atoms M (e.g., Mg in MgB2) as capacitors, which reduce the condensation-energy loss due to the charging energy E_c between the B-B layers. In the viewpoint of the present model, the recently discovered 117-Kelvin superconductor C60/CHBr3 is also discussed in terms of the intercalation molecules CHBr3 as possible capacitors among the superconducting grains of C60 molecules.

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Chikao Kawabata, Nobuhiko Hayashi, Fumihisa Ono. 2001-09-13. Critical Temperature T_c versus Charging Energy E_c in MgB2 and C60/CHBr3. https://doi.org/10.1016/s0921-4534(02)01416-8

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