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 (KF) can be used to improve the bounds on the magnitude of the nonminimal coupling, λ(KσF), by the factors 105 or 1025. The nonminimal coupling also generates higher-order derivative contributions to the gauge field effective action quadratic terms.