Fig. 2: X-ray absorption spectroscopy (XAS) of FeSe/ETO.
a XAS of Eu M4,5 edge at 2 K in the field of 6.8 T, measured with circularly polarized photons. The incident direction and magnetic field are perpendicular to the sample surface. b X-ray magnetic circular dichroism (XMCD) at the Eu M4,5 edges at 2 K in various magnetic fields. c XMCD at the Eu M4,5 edges in the field of 6.8 T at various temperatures. d The magnetization contributed by spins on Eu atoms as a function of magnetic field and temperature. The points are the data extracted from the XMCD spectra using the sum rules. The lines are the XMCD intensities at the Eu M5 peak measured with sweeping field, and normalized to the sum-rule values at 6.8 T for each temperature. e X-ray linear dichroism (XLD) at the Eu M4,5 edges at zero field at 2 K and 20 K. The incident direction is 60° from the surface normal. f XAS and XMCD at the Ti L2,3 edges measured with circularly polarized photons. g XAS and XMCD at the Fe L2,3 edges measured with circularly polarized photons. h Illustration of the spin alignment in the FeSe/ETO heterostructures with different external fields.
