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Comment on ``Enhancement of the Tunneling Density of States in Tomonaga-Luttinger Liquids''

Michele Fabrizio·Alexander O. Gogolin
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Abstract

In a recent Physical Review Letter, Oreg and Finkel'stein (OF) have calculated the electron density of states (DOS) for tunneling into a repulsive Luttinger liquid close to the location of an impurity. The result of their calculation is a DOS which is enhanced with respect to the pure system, and moreover diverging for not too strong repulsion. In this Comment we intend to show that OF's calculation suffers from a subtle flaw which, being corrected, results into a DOS not only vanishing at zero frequency but in fact suppressed in comparison with the DOS of a pure Luttinger liquid.

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Michele Fabrizio, Alexander O. Gogolin. 1997-02-10. Comment on ``Enhancement of the Tunneling Density of States in Tomonaga-Luttinger Liquids''. https://doi.org/10.1103/physrevlett.78.4527

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