Title :
Thermal effects in small metallic particles
Author :
Veitch, R.J. ; Richter, H.J. ; Poganiuch, P. ; Jakusch, H. ; Schwab, E.
Author_Institution :
BASF AG, Ludwigshafen, Germany
fDate :
11/1/1994 12:00:00 AM
Abstract :
The process of thermally assisted switching in small metallic particles is studied by measuring the field dependent fluctuation fields. A correlation is found between the size of crystallographic sub-units rather than the total volume of the particles and the fluctuation fields. Therefore, very small particles can be more stable magnetically than large particles, if they contain only few large crystal grains. The grain volumes are determined by X-ray line broadening measurements on random and on oriented samples. The effect of thermal activation on the switching process is confirmed by measuring the recording currents needed to optimize high frequency output in tape samples prepared with the same particles
Keywords :
X-ray diffraction; magnetic particles; magnetic switching; magnetocaloric effects; X-ray line broadening; crystal grains; crystallographic sub-unit size; currents; fluctuation fields; grain volumes; high frequency output; magnetic stability; oriented samples; particle volume; random samples; small metallic particles; tape samples; thermal activation; thermal effects; thermally assisted switching; Iron; Magnetic field measurement; Magnetic properties; Magnetic recording; Magnetization; Particle measurements; Size measurement; Switches; Time measurement; Volume measurement;
Journal_Title :
Magnetics, IEEE Transactions on
