Wish starts successful operations
22 Feb 2010




Wish, the new magnetic powder and single crystal diffractometer at the ISIS second target station is fully operational and hosted its first external users in December 2009.

Roger Johnson, Tom Frawley (Durham University) and Pascal Manuel (ISIS) look over Wish whilst it performs its first experiment.

A collaborative study between Durham University (UK) and Campinas University (Brazil) used Wish to investigate magnetic structures inTm2CoGa8 and Er2CoGa8 .at milli-kelvin temperatures. It is the first instrument in the second target station to achieve these conditions.

PhD student Roger Johnson and MSci student Tom Frawley, both from Durham University, spent time at ISIS to implement the study on the inter-metallic compounds.

The neutron powder patterns Wish provided were of very high quality, despite the samples being experimentally difficult to measure due to their high neutron absorption. Rietveld refinement of the data has enabled the magnetic structure of both compounds to be determined.

Materials such as these inter-metallic compounds are at the forefront of solid-state research due to a number of them showing novel superconductivity, heavy fermion behaviour and quantum criticality. It is hoped that these findings will make a significant contribution to future understanding of this specific series of materials.

“The understanding of the microscopic behaviour of inter-metallic compounds is very important. Systems that exhibit heavy fermion behaviour and quantum criticality are currently of fundamental scientific interest,” Roger said.

“A microscopic explanation of the magnetic structures measured on Wish may also be transferable to other, more complex systems of technological interest,” he added.

Pascal Manuel, an Instrument Scientist for Wish said, “Everything is running very smoothly, and we hope for a long and successful user schedule to evolve.”

“These results give hints that rapid collection of diffraction patterns on small or absorbing samples in complex sample environments could become routine at ISIS.”

Since this first experiment, further successful experiments have been completed and scientific results have been submitted for publication.