Pulsed-field

The Pulsed Field setup is one of three instruments at the UE46_PGM-1 beamline. It allows to perform X-ray absorption spectroscopy (XMCD/XLD) and resonant soft X-ray scattering in magnetic fields up to 30 Tesla. XAS is measured with the field along the X-ray beam direction. The instrument also comprises a UHV-compatible two-circle diffractometer operating in horizontal scattering geometry.

Selected Applications:

• Element-specific hysteresis loops up to 30 T
• XMCD from hard magnetic materials
• Diffraction from complex electronic superstructures (magnetic, charge and orbital order)

Pulsed Field setups and results

Methods

Elastic Scattering, Magnetic Scattering, Reflectivity, REXS, XMCD, XMLD

Remote access

not possible

Instrument for Dichroic Soft X-ray Absorption and Scattering in Very High Magnetic Fields

The Pulsed Field setup allows to perform X-ray absorption spectroscopy (XMCD/XMLD) and resonant soft X-ray scattering in magnetic fields up to 30 Tesla and temperatures down to 10 K. The central part of the instrument is a small 30 T magnet powered by a capacitor bank of 9.6 mF / 2.4 mF, resulting in magnet pulses between 1 ms and 5 ms duration.

X-ray absorption spectra are measured by total electron yield via drain current. The magnetic field is directed along the X-ray beam (longitudinal geometry only).

Soft X-ray scattering is performed with a two-circle diffractometer operating in horizontal scattering geometry using a Si photodiode as detector. The accessible angular range and magnetic field direction find some limitation depending on the magnet design. Available scattering geometries will be expanded.

The strong magnet pulse leads to a non-negligible mechanical response of the sample holder by coupling to the magnetic moment of the sample. In order to reduce perturbation effects on the signal, the sample volume must therefore be minimized. For XAS, sample size will typically be 0.5 mm x 0.5 mm x 0.5 mm, thin films are easier to handle.