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Endohedral Impurities in Carbon Nanotubes

Dennis P. Clougherty
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Abstract

A generalization of the Anderson model that includes pseudo-Jahn-Teller impurity coupling is proposed to describe distortions of an endohedral impurity in a carbon nanotube. Treating the distortion within mean-field theory, spontaneous axial symmetry breaking is found when the vibronic coupling strength g exceeds a critical value g$_c$. The effective potential in the symmetry-broken state is found to have O(2) symmetry, in agreement with numerical calculations. For metallic zigzag nanotubes endohedrally-doped with transition metals in the dilute limit, the low-energy properties of the system may display two-channel Kondo behavior; however, strong vibronic coupling is seen to exponentially suppress the Kondo energy scale.

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Dennis P. Clougherty. 2002-12-12. Endohedral Impurities in Carbon Nanotubes. https://doi.org/10.1103/physrevlett.90.035507

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