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arXiv · 1704.04148

Low-energy effective action in two-dimensional SQED: A two-loop analysis

I. B. Samsonov
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Abstract

We study two-loop quantum corrections to the low-energy effective actions in N=(2,2) and N=(4,4) SQED in the Coulomb branch. In the latter model, the low-energy effective action is described by a generalized Kahler potential which depends on both chiral and twisted chiral superfields. We demonstrate that this generalized Kahler potential is one-loop exact and corresponds to the N=(4,4) sigma-model with torsion presented by Rocek, Schoutens and Sevrin. In the N=(2,2) SQED, the effective Kahler potential is not protected against higher-loop quantum corrections. The two-loop quantum corrections to this potential and the corresponding sigma-model metric are explicitly found.

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I. B. Samsonov. 2017-04-21. Low-energy effective action in two-dimensional SQED: A two-loop analysis. https://doi.org/10.1007/jhep07(2017)146

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