Compact Rotating In-Plane HTS Magnet for X-Ray Scattering Sample Environment

We report the design and testing of a compact 0.8-T magnet for x-ray magnetic scattering and x-ray magnetic circular dichroism experiments; the magnet can be physically rotated around a stationary sample to provide field rotation in the plane of the sample. Taking an H-frame design split horizontally in the sample plane, the resulting optical access is over 270°, delivering greater than 180° scattering angle over the total field-angle range, and with an axial (out of plane) opening angle of over 8 degrees. To provide compatibility with an existing ultrahigh-vacuum chamber, the magnet was designed in the form of a long cylinder, with an outer diameter restricted to less than 150 mm and with a sample bore close to 32 mm in diameter. To meet the challenging dimensional and optical access requirements, a partial magnetic circuit was employed with second-generation high-temperature superconducting (HTS) coils utilized for their high engineering current density. This magnet exemplifies the compact high-performance magnets that are possible with HTS technology.