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Conductance renormalization and conductivity of a multi-subband Tomonaga-Luttinger model

Takashi Kimura
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Abstract

We studied the conductance renormalization and conductivity of multi-subband Tomonaga-Luttinger models with inter-subband interactions. We found that, as in single-band systems, the conductance of a multi-subband system with an arbitrary number of subbands is not renormalized due to interaction between electrons. We derived a formula for the conductivity in multi-subband models. We applied it to a simplified case and found that inter-subband interaction enhances the conductivity, which is contrary to the intra-subband repulsive interaction, and that the conductivity is further enhanced for a larger number of subbands.

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Takashi Kimura. 2001-09-06. Conductance renormalization and conductivity of a multi-subband Tomonaga-Luttinger model. https://doi.org/10.1103/physrevb.64.233306

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