DIFFERENTIAL PHASE-CONTRAST IN TEM

We present the first results using a novel transmission electron micro scope (TEM) technique that combines electron holography and Fresnel im aging to give simultaneous information about magnetization and domain wall position in magnetic materials. This technique provides different ial phase contrast through electron holography in a manner similar to the established differential mode in scanning transmission electron mi croscopy. It has been implemented by placement of an electrostatic bip rism in the condenser aperture plane of a field emission TEM. Changes of one in-plane component of the magnetic field of a Co specimen have been imaged. With rotation of either the biprism or the specimen, it s hould be possible to map the entire in-plane magnetic field.