Jahresbericht 2005 - IPHT Jena

22
MAGNETIK & QUANTENELEKTRONIK / MAGNETICS & QUANTUM ELECTRONICS
Fig. 1.10: Probability P(j) for a coupling energy
density between j and (j+dj) as a function of j,
determined from torque measurements with a
NiFe / IrMn film at T = 10 K.
Fig. 1.10 shows the distribution function P(j) for a
sputtered NiFe (16 nm) / IrMn (0.8 nm) coupled
film determined from torque measurements at
T = 10 K. Only the range of coupling j > j 1, which
is responsible for the irreversible torque contributions,
can be recorded by the method. The result
shows that most of the grains have low coupling
energies and that the portion of strongly coupled
grains continuously decreases with increasing j.
The value of K used was estimated using information
from exchange bias measurements.
1.2.8 Electron excited L X-ray spectra of
the elements 14