F. D'Orazio et al., Temperature dependence of magnetic properties in epitaxial Cu/Ni/Cu/Si (111) measured by magneto-optical Kerr effect, J MAGN MAGN, 199, 1999, pp. 369-371
We report on magneto-optical Kerr effect (MOKE) measurements performed in t
he range 4-300 K on five epitaxial Cu/Ni/Cu/Si (1 1 1) heterostructures, gr
own by UHV evaporation, with the Ni layer thickness d varying in the range
between 30 and 10 Angstrom. In a previous work, we showed that, at room tem
perature, the magnetization lies preferentially in-plane for d greater than
or equal to 30 Angstrom while it switches out-of-plane when 15 less than o
r equal to d less than or equal to 25 Angstrom. In this work, we show that
on further reducing the film thickness the magnetization undergoes a second
reorientation transition. For d = 10 Angstrom an in-plane magnetization is
found with a coercive field which becomes negligible above 200 K. No orien
tation transition is observed as a function of temperature for any of the s
pecimens analyzed. However, the estimated coercive field and the loop squar
eness decrease monotonically with increasing temperature. (C) 1999 Elsevier
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