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Register a new userA layering model for superconductivity in the borocarbides
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Added by
Thereza Cristina de Lacerda Paiva
Publication date
2003
fields
Physics
and research's language is
English
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We propose a superlattice model to describe superconductivity in layered materials, such as the borocarbide families with the chemical formulae $RT_2$B$_2$C and $RT$BC, with $R$ being (essentially) a rare earth, and $T$ a transition metal. We assume a single band in which electrons feel a local attractive interaction (negative Hubbard-$U$) on sites representing the $T$B layers, while U=0 on sites representing the $R$C layers; the multi-band structure is taken into account minimally through a band offset $epsilon$. The one-dimensional model is studied numerically through the calculation of the charge gap, the Drude weight, and of the pairing correlation function. A comparison with the available information on the nature of the electronic ground state (metallic or superconducting) indicates that the model provides a systematic parametrization of the whole borocarbide family.
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