Time - resolved wide - field Kerr microscopy on magnetic thin film elements

Soft magnetic thin film elements play a central role in sensor and computer applications. The magnetic state of an element is either probed inductively in an integrated pick-up loop or by measuring the magnetoresistance (MR) of the element, applied in magnetoresistive sensors or MR read heads. In most modern devices the giant or tunneling magnetoresistance effects are used, which rely on the spin-dependent scattering or tunneling, respectively, of electrons in multilayer systems consisting of alternating ferromagnetic and nonmagnetic layers. The discovery of these effects has triggered huge worldwide research and development activities in the last decade, which in recent years focus on Magnetic Random Access Memories (MRAMs). The MRAM storage principle relies on the fact that a magnetic element can exist in two oppositely magnetized, nearly-saturated metastable states. By current pulses in crossed word and bit lines, the magnetization of single elements (representing the Dmitry Chumakov, Jeffrey McCord, Rudolf Schäfer, Ludwig Schultz