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arXiv · 1510.04704

Electronic Pair-Binding and Hund's Rule Violations in Doped $C_{60}$

Hong-Chen Jiang·Steven Kivelson
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Abstract

We calculate the electronic properties of the $t$-$J$ model on a $C_{60}$ molecule using the density-matrix renormalization group and show that Hund's first rule is violated and that for an average of three added electron per molecule, an effective attraction (pair-binding) arises for intermediate values of $t/J$. Specifically, it is energetically favorable to put four electrons on one $C_{60}$ and two on a second rather than putting three on each. Our results show that a dominantly electronic mechanism of superconductivity is possible in doped $C_{60}$.

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Hong-Chen Jiang, Steven Kivelson. 2015-10-15. Electronic Pair-Binding and Hund's Rule Violations in Doped $C_{60}$. https://doi.org/10.1103/physrevb.93.165406

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