Magnetic microstructure of magnetotactic bacteria by electron holography
Off-axis electron holography in the transmission electron microscope was used to correlate the physical and magnetic microstructure of magnetite nanocrystals in magnetotactic bacteria. The magnetite crystals were all single magnetic domains, and the magnetization directions of small superparamagnetic crystals were constrained by magnetic interactions with larger crystals in the chains. Shape anisotropy was found to dominate magnetocrystalline anisotropy in elongated crystals. A coercive field between 300 and 450 oersted was determined for one chain.
Dunin-Borkowski
RE
R. E. Dunin-Borkowski and M. R. McCartney, Center for Solid State Science, Arizona State University, Tempe, AZ 85287-1704, USA. R. B. Frankel, Department of Physics, California Polytechnic State University, San Luis Obispo, CA 93407, USA. D.
McCartney
MR
Frankel
RB
Bazylinski
DA
Posfai
M
Buseck
PR