"Electronic pair binding and Hund's rule violations in doped C60"

Hong-Chen Jiang: Steven Kivelson; Physical Review B, 04/05/16.

Additional Authors: Steven Kivelson

Abstract:

We calculate the electronic properties of the tJ model on a C60 molecule using the density-matrix renormalization group and show that Hund’s first rule is violated and that for an average of three added electrons 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 C60 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 C60.