Table-top soft x-ray polarimetry setup with rotatable linearly polarized light source

Abstract

A table-top soft x-ray polarimetry setup has been developed at the Institute of Precision Optical Engineering for characterizing the polarization properties of mirrors designed for the lightweight asymmetry and magnetism probe project. Based on a Co/C multilayer polarizer mirror, linearly polarized soft x-rays were generated at a wavelength of 4.48 nm, which could be rotated around the beam-propagation direction by using a differentially pumped rotary feedthrough. The setup design and the alignment method are described in detail. The capabilities of this spectrometer were demonstrated through a polarization test on a twin Co/C multilayer polarizer sample, and the results agree well with the expected sine wave.