Pulsed fields

While magnetic fields are widely used to perturb, tune, and characterise the electronic and magnetic interactions in many of today’s most interesting materials, ultrahigh magnetic fields are required for the study of strongly interacting systems, as well as to overcome the small sample sizes or significant levels of disorder that typify the newest compounds. Pulsed magnet technology allows ultrahigh fields to be achieved for a short space of time and is the only way to generate fields greater than 45 tesla.

A 0.8 MJ capacitor bank supplies the current that drives the Oxford pulsed magnets.

As well as making full use of international high-magnetic-field facilities, members of the group are lucky that Oxford Physics is the host of the Nicholas Kurti High Magnetic Field Laboratory , currently the only experimental facility in the UK where a wide range of quantum materials can be explored using magnetic fields in excess of 25 T. Here, electronic, magnetic and optical measurements are possible in fields up to 60 T and temperatures as low as 300 mK.

Example data: Field-induced phases are explored in the frustrated magnet TmAgGe using pulsed magnets

More example data: Top: an organic superconductor exhibits quantum oscillations at 600 mK. Bottom: the magnetization of a complex oxide material is measured at 1.5 K

Experimental capabilities

  • Compensated coil magnetometry: measurements of absolute magnetization in milligram samples of magnetic material. This technique is highly sensitive to magnetic phase transitions and energy level crossings.
  • Electronic transport: measurements of resisitivity, skin-depth and penetration-depth of metallic and superconducting systems using contacted and contactless methods.
  • Fermiology: measurements of the Fermi surface of conducting materials using de Haas-van Alphen and Shubnikov-de Haas quantum oscillation effects.
  • 3He refrigerators enable experiments to take place at temperatures down to 400 millikelvin.