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Exact Fermi-edge singularity exponent in a Luttinger liquid

Andrei Komnik·Reinhold Egger·Alexander O. Gogolin
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Abstract

We report the exact calculation of the Fermi-edge singularity exponent for correlated electrons in one dimension (Luttinger liquid). Focusing on the special interaction parameter g=1/2, the asymptotic long-time behavior can be obtained using the Wiener-Hopf method. The result confirms the previous assumption of an open boundary fixed point. In addition, a dynamic k-channel Kondo impurity is studied via Abelian bosonization for k=2 and k=4. It is shown that the corresponding orthogonality exponents are related to the orthogonality exponent in a Luttinger liquid.

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Andrei Komnik, Reinhold Egger, Alexander O. Gogolin. 1997-02-27. Exact Fermi-edge singularity exponent in a Luttinger liquid. https://doi.org/10.1103/physrevb.56.1153

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