ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
We report on the magnetic properties of Dy(t A(ring))/Mo(d A(ring)), DyCo(t A(ring))/Mo(d A(ring)), and Gd(t A(ring))/Mo(d A(ring)) multilayers where d=180 A(ring) and t ranges from 10 to 3000 A(ring). We find a decrease in Tc with decreasing t, with the most rapid decrease occurring for the Gd system where the anisotropy is the weakest. We have looked at the time dependence of magnetization in the anisotropic systems (Dy based). At long times (5×104 s) the magnetization shows a stretched exponential dependence on time as is found in other magnetically disordered systems. We have also looked at the rate of magnetic relaxation at short times (〈1000 s) and find that it becomes independent of temperature below a temperature in the range 3–6 K depending on the magnetic layer thickness t. We shall consider the possibility of macroscopic quantum tunneling here and estimate the temperature, T*, below which a system is expected to cross over from thermally activated to quantum tunneling.1,2 We shall also compare our results to previous work on Dy/Cu.3
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.355622
