On effective K\"ahler potential in N=2, d=3 SQED

TL;DR

This paper calculates the two-loop effective K"ahler potential in three-dimensional N=2 supersymmetric electrodynamics with a Chern-Simons term, demonstrating gauge independence and developing a new computational method.

Contribution

It introduces a novel approach to compute the two-loop effective K"ahler potential in N=2, d=3 SQED, handling gauge dependence and complex supergraph calculations.

Findings

Two-loop effective K"ahler potential computed

Result is gauge parameter independent

Developed an efficient supergraph calculation procedure

Abstract

We compute the two-loop effective K\"ahler potential in three-dimensional N=2 supersymmetric electrodynamics with Chern-Simons kinetic term for the gauge superfield. The effective action is constructed on the base of background field method with one parametric family of gauges. In such an approach, the quadratic part of quantum action mixes the gauge and matter quantum superfields yielding the complications in the computations of the loop supergraphs. To avoid this obstacle and preserve dependence on the gauge parameter we make a nonlocal change of quantum matter superfields after which the propagator is diagonalized, however the new vertices have appeared. We fix the suitable background and develop the efficient procedure of calculating the two-loop supergraphs with the new vertices. We compute the divergent and finite parts of the superfield effective action, find the two-loop effective K\"ahler potential and show that it does not depend on the gauge parameter.