Temperature-dependent proximity magnetism in Pt

We study experimentally the magnetic coupling between ferromagnets separated by a thin Pt layer. The coupling remains ferromagnetic regardless of the Pt thickness and exhibits a significant dependence on temperature. We show that these results are consistent with the effects of temperature-dependent magnetism induced in Pt at the interfaces with ferromagnets. Analysis shows that the characteristic magnetization decay length in Pt increases from approximately 0.2 nm at room temperature to 0.8 nm at 25 K.