Off-axis electron holography of single ferromagnetic nanowires

Off-axis electron holography has been applied to study the remanent magneti zation state of single ferromagnetic Co93Cu7 nanowires a few micrometer in length and a typical radius of 40nm. Because the objective lens of the elec tron microscope has to be switched off, the spatial resolution of the recon structed phase images is presently limited to approximately 70nm. The magne tization reversal of an individual nanowire has been followed by observing a series of remanent states, obtained ex situ by applying different externa l magnetic field sweeps parallel to the nanowire axis. The relation between misoriented crystal grains and nonuniform magnetization states has been st udied by the combination of electron holography and conventional transmissi on electron microscopy. (C) Elsevier Science Inc., 1999. All rights reserve d.