Premium
Scanning Tunneling Spectroscopy Study of Temperature‐Dependent Magnetization Switching Dynamics in Magnetic Nanoparticle Arrays
Author(s) -
Tirosh Einat,
Taub Nurit,
Majetich Sara A.,
Markovich Gil
Publication year - 2008
Publication title -
israel journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.908
H-Index - 54
eISSN - 1869-5868
pISSN - 0021-2148
DOI - 10.1560/ijc.48.2.81
Subject(s) - magnetization , condensed matter physics , chemistry , scanning tunneling microscope , magnetite , nanoparticle , magnetic nanoparticles , magnetization dynamics , scanning tunneling spectroscopy , quantum tunnelling , nanotechnology , magnetic field , materials science , physics , quantum mechanics , metallurgy
Scanning tunneling microscopy measurements were performed on close‐packed arrays of surfactant‐capped magnetite (Fe 3 O 4 ) nanocrystals. Current noise measurements over individual nanoparticles (NPs) at 2–3‐particle‐thick positions displayed enhanced low‐frequency noise power around the magnetization blocking temperature of the array. This noise originated in a time‐varying spin filter effect due to slow magnetization switching of individual particles in the arrays, changing their magnetization orientation with respect to their neighbors. The magnetite nanocrystals, being half‐metallic, highly spin‐polarized conductors, enabled this new observation. Consequently, this type of experiment may provide new insight into the microscopic details of magnetization dynamics in strongly interacting arrays of dipoles, which resemble spin‐glasses.