Radiative generation of the CPT-even gauge term of the SME from a dimension-five nonminimal coupling term

In this Letter we show for the first time that the usual CPT-even gauge term of the Standard Model Extension (SME), in its full structure, can be radiatively generated, in a gauge invariant level, in the context of a modified QED endowed with a dimension-five nonminimal coupling term recently proposed in the literature. As a consequence, the existing upper bounds on the coefficients of the tensor (K-F) can be used to improve the bounds on the magnitude of the nonminimal coupling, lambda(K-sigma F), by the factors 10(5) or 10(25). The nonminimal coupling also generates higher-order derivative contributions to the gauge field effective action quadratic terms. (C) 2013 Elsevier B.V. All rights reserved.