Generation of circularly polarized radiation from a compact plasma-based EUV light source for tabletop X-ray magnetic circular dichroism studies

Generation of circularly polarized light in the extreme ultraviolet (EUV) spectral region (about 25 eV-250 eV) is highly desirable for applications in spectroscopy and microscopy but very challenging to achieve in a smallscale laboratory. In this spectral range, the 3p absorption edges of Fe (54 eV), Co (60 eV) and Ni (67 eV) offer a high magnetic contrast often employed for magneto-optical and electron spectroscopies as well as for magnetic imaging. We simulated and designed an instrument capable of generating both linearly and circularly polarized EUV radiation and performed polarimetric measurements of the degree of linear and circular polarization. Furthermore, for the first time, we demonstrate measurements of the X-ray magnetic circular dichroism (XMCD) at the Co 3p absorption edge with a plasma-based EUV light source.