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arXiv · 0804.4108

Coupling-geometry-induced temperature scales in the conductance of Luttinger liquid wires

P. Wächter·V. Meden·K. Schönhammer
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Abstract

We study electronic transport through a one-dimensional, finite-length quantum wire of correlated electrons (Luttinger liquid) coupled at arbitrary position via tunnel barriers to two semi-infinite, one-dimensional as well as stripe-like (two-dimensional) leads, thereby bringing theory closer towards systems closer to setups realized in experiments. In particular, we compute the temperature dependence of the linear conductance $G$ of a system without bulk impurities. The appearance of new temperature scales introduced by the lengths of overhanging parts of the leads and the wire implies a $G(T)$ which is much more complex than the power-law behavior described so far for end-coupled wires. Depending on the precise setup the wide temperature regime of power-law scaling found in the end-coupled case is broken up in up to five fairly narrow regimes interrupted by extended crossover regions. Our results can be used to optimize the experimental setups designed for a verification of Luttinger liquid power-law scaling.

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P. Wächter, V. Meden, K. Schönhammer. 2009-04-14. Coupling-geometry-induced temperature scales in the conductance of Luttinger liquid wires. https://doi.org/10.1088/0953-8984%2F21%2F21%2F215608

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