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arXiv · 0909.5048

The embedding method beyond the single-channel case: Two-mode and Hubbard chains

Axel Freyn·Gabriel Vasseur·Peter Schmitteckert·Dietmar Weinmann·Gert-Ludwig Ingold·Rodolfo A. Jalabert·Jean-Louis Pichard
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Abstract

We investigate the relationship between persistent currents in multi-channel rings containing an embedded scatterer and the conductance through the same scatterer attached to leads. The case of two uncoupled channels corresponds to a Hubbard chain, for which the one-dimensional embedding method is readily generalized. Various tests are carried out to validate this new procedure, and the conductance of short one-dimensional Hubbard chains attached to perfect leads is computed for different system sizes and interaction strengths. In the case of two coupled channels the conductance can be obtained from a statistical analysis of the persistent current or by reducing the multi-channel scattering problem to several single-channel setups.

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Axel Freyn, Gabriel Vasseur, Peter Schmitteckert, Dietmar Weinmann, Gert-Ludwig Ingold, Rodolfo A. Jalabert, Jean-Louis Pichard. 2009-09-28. The embedding method beyond the single-channel case: Two-mode and Hubbard chains. https://doi.org/10.1140/epjb/e2010-00153-y

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