Non-trapping magnetic fields and Morrey-Campanato estimates for Schrodinger operators

We prove some uniform in c a priori estimates for solutions of the equation (del - iA)(2)u - V(x)u + (lambda +/- i epsilon)u = f, lambda >= 0. epsilon not equal 0. The estimates are obtained in terms of Morrey-Campanato norms, and can be used to prove absence of zero-resonances, in a suitable sense, for electromagnetic Hamiltonians. Quantitative conditions on the size of the trapping component of the magnetic field and the non-repulsive component of the electric field are given. (C) 2009 Elsevier Inc. All rights reserved.