We use spin-resolved electron tunneling to study the exchange field in the Al component of EuS/Al bilayers, in both the superconducting and normal-state phases of the Al. Contrary to expectation, we show that the exchange field Hex is a nonlinear function of applied field, even in applied fields that are well beyond the EuS coercive field. Furthermore, the magnitude H ex is unaffected by the superconducting phase. In addition, H ex decreases significantly with increasing temperature in the temperature range of 0.1-1 K. We discuss these results in the context of recent theories of generalized spin-dependent boundary conditions at a superconductor-ferromagnet interface. © 2011 American Physical Society.
Publication Source (Journal or Book title)
Physical Review Letters
Xiong, Y., Stadler, S., Adams, P., & Catelani, G. (2011). Spin-resolved tunneling studies of the exchange field in EuS/Al bilayers. Physical Review Letters, 106 (24) https://doi.org/10.1103/PhysRevLett.106.247001