The role of interfaces in the behavior of magnetic tunnel junction structures

Abstract

Abstract Magnetic tunnel junctions are nanoscale oxide heterostructures that exhibit the phenomenon of tunnel magnetoresistance. The transport and magnetic behavior of these structures depends critically on parameters such as the layer thickness and the roughness and chemical abruptness of the interfaces between the layers, which are nanometer-scale in thickness. We have used high resolution electron microscopy, transmission electron microscopy chemical mapping and atom probe tomography to understand the microstructural origins of the magnetic and transport properties of magnetoresistive structures. We have also used in-situ transmission electron microscopy nanobiasing experiments to probe the local transport properties of magnetic tunnel junctions as a function of processing conditions.