Abstract:
A technique for probing the sample interior using the leading edge of an alternating evanescent magnetic field is suggested. It makes it possible to highlight and study physical processes taking place at the vortex front in superconductors. Successively increasing the field amplitude by equal amounts, one can study the formation and transformation of the magnetic microstructure in response to variation of the sample’s crystal microstructure. For samples with different microstructures, qualitatively new results are obtained. The technique suggested may be used for testing high-temperature superconductor epitaxial films and magnetic materials.