SPIN POLARIZATION IN CU CORE-LEVEL PHOTOEMISSION WITH LINEARLY POLARIZED SOFT X-RAYS

We report on the first observation of electron spin polarization in ph otoemission from inner shells of a nonmagnetic solid with linearly pol arized radiation. The effect is observed in normal emission from the 2 p and 3p core levels of Cu(001) excited with p-polarized soft-x-ray ra diation at oblique incidence. We interpret the effect in terms of spin -orbit interaction and interference of continuum partial waves. The re sults are relevant for the understanding of magnetic dichroism and spi n polarization in core-level photoemission from ferromagnets.