It’s official – Guinness World Records have officially confirmed that a team of engineers led by Cambridge’s Professor David Cardwell created the strongest trapped field (17.6 tesla!) in a superconductor back in 2014.
Guinness credited the achievement to researchers from the University of Cambridge (UK), the National High Magnetic Field Laboratory and the Boeing Company (both USA) whose findings were originally published Superconductor Science and Technology back in June 2014.
The team were able to create a magnetic field trapped in a superconductor at 17.6 tesla (a tesla is the standard unit of magnetic flux density). This is equivalent to three tonnes of force inside a golf ball-sized object and compares to a small bar magnet which produced a field of only 0.01 Tesla.
The result was achieved using gadolinium boron carbon oxide (GdBCO). Normally, this material is as brittle as China – but the team were able to dope the structure with silver, and ‘shrink wrapping’ steel around it making it much stronger. The object itself is about the size our thumb.
The previous record of 17.2 tesla had stood for almost a decade.
The research is important as superconductors which can trap magnetic fields have a wide variety of applications; from flywheels for energy storage, ‘magnetic separators’, which can be used in mineral refinement and pollution control, to high-speed Maglev trains.
Published as “Modelling and comparison of trapped fields in (RE)BCO bulk superconductors for activation using pulsed field magnetisation” in Superconductor Science and Technology Number 6, June 2014 (063001-065019)
Interested in Superconductors?
David Cardwell, Cambridge’s lead researcher on the project, is giving this year’s Foundation Lecture on 17 November at 6pm, entitled ‘Bulk superconductors: revolution or red herring?’
David Cardwell is a Fellow of Fitzwilliam College. He is giving the annual Foundation Lecture on 17 November at 6pm, entitled “Bulk superconductors: revolution or red herring?”:
The discovery of the so-called High Temperature Superconductors in 1987, which in bulk forms are able to conduct very high electrical currents and hence generate extremely high magnetic fields at liquid nitrogen temperatures, was heralded as the most significant scientific breakthrough since the discovery of the transistor. This lecture will describe in a substantially non-mathematical way the properties of these remarkable materials, their manufacture and their potential for engineering applications, which include frictionless bearings, energy storage systems, MRI and high field permanent magnets.
The lecture is free to attend on Thursday 17 November at 6:00 pm in Fitzwilliam College Auditorium in Cambridge. However, while the cost is free bookings must be made online to secure a place.