March 2005

A 10T Superconducting Magnet for Magneto-Structural and Magneto-Electronic Research and Education

The magnet set up at X19A. It is mounted on a xyz table, which can be motor-controlled for ease of alignment. Samples are loaded from the top on a vertical rod into the samples space and are cooled by helium vapor or liquid from the magnet reservoir.

A horizontal-field, split-coil superconducting magnet has become available for magneto-structural and magneto-electronic research at the NSLS. The magnet can operate over the temperature range from 1.6 to 300 K and over the field range 0 to 10 T. The horizontal field enables x-ray absorption measurements with linearly polarized x-rays with the electric field of the beam parallel to or normal to the magnetic field. Care was taken in the design to ensure that the samples can be measured in transmission mode for energies down to 5 keV (and in small steel hutches).

In general, this magnet is being used to study the lattice-spin coupling in complex materials. It was designed to be used on beamlines X11A, X19A, X21A and X23B for structural measurements (XAFS and powder XRD) in magnetic fields. With the use of a quarter wave plate, hard x-ray circular dichroism measurements on these beamlines will be feasible. With a differential pumping configuration, a future upgrade will make possible x-ray magnetic x-ray magnetic circular dichroism (XMCD) measurements on beamlines X13A U4B. This will enable the study of magnetism in hard magnets as well as the induced moments on oxygen sites in metal oxide systems. Optical access is possible by replacing the kapton windows with quartz windows and/or replacing the variable temperature insert windows and external windows with all-quartz windows. The magnet was funded by a NSF IMR Grant and is now operational.