Quantitative in situ magnetization reversal studies in Lorentz microscopy and electron holography

A generalized procedure for the in situ application of magnetic fields by means of the excitation of the objective lens for magnetic imaging experiments in Lorentz microscopy and electron holography is quantitatively described. A protocol for applying magnetic fields with arbitrary in-plane magnitude and orientation is presented, and a freeware script for Digital Micrograph¿ is provided to assist the operation of the microscope. Moreover, a method to accurately reconstruct hysteresis loops is detailed. We show that the out-of-plane component of the magnetic field cannot be always neglected when performing quantitative measurements of the local magnetization. Several examples are shown to demonstrate the accuracy and functionality of the methods.
This work was supported by the Spanish Ministry of Economy and Innovation (MINECO) through Projects MAT2009-08771, MAT2011-28532-C03-02, MAT2011-28532-C03-03 and MAT2011-27553-C02 including FEDER funding, by the Aragón Regional Government through Projects E26 and CTPP4/11, and the European Union under the Seventh Framework Programme under a contract for an Integrated Infrastructure Initiative, Reference 312483-ESTEEM2.