ISIS Neutron and Muon Source Data Journal

This is a page describing data taken during an experiment at the ISIS Neutron and Muon Source. Information about the ISIS Neutron and Muon Source can be found at https://www.isis.stfc.ac.uk.


Charting the increase in spin fluctuations as we approach the critical point in the itinerant ferromagnet, LaFe13-xSix

Abstract: The LaFe13-xSix system (x<1.6) has a first order ferromagnetic, FM, to paramagnetic, PM, transition that is tunable in magnetic field, ending at a (tri)critical point (Hcrit, Tcrit) beyond which it is second order. We have shown using an ac calorimetry technique that giant changes in the heat capacity occur in this material and that it exhibits a maximum at the critical point. Previous measurements with MARI showed an increase in diffuse scattering around Tc; in line with our observations from ac calorimetry. This change in heat capacity is maximum at the critical point, therefore we expect an increase in the amplitude of inelastic scattering as the applied magnetic field is increased. As such, the key objectives here are (a) to observe whether we such an increase occurs and (b) to correlate the increase in scattering with the simultaneous (>1%) volume change of the material.

Principal Investigator: Dr Kelly Morrison
Experimenter: Professor Lesley Cohen
Experimenter: Dr Oliver Gutfleisch
Experimenter: Dr Karl Sandeman
Experimenter: Professor Stephen Hayden
Experimenter: Dr Andrew Caruana
Local Contact: Dr Russell Ewings

DOI: 10.5286/ISIS.E.RB1320200

ISIS Experiment Number: RB1320200

Part DOI Instrument Public release date Download Link
10.5286/ISIS.E.42581235 LET 10 December 2016 Download
10.5286/ISIS.E.69549791 LET 28 November 2018 Download

Publisher: STFC ISIS Neutron and Muon Source

Data format: RAW/Nexus
Select the data format above to find out more about it.

Data Citation

The recommended format for citing this dataset in a research publication is as:
[author], [date], [title], [publisher], [doi]

For Example:
Dr Kelly Morrison et al; (2013): Charting the increase in spin fluctuations as we approach the critical point in the itinerant ferromagnet, LaFe13-xSix, STFC ISIS Neutron and Muon Source, https://doi.org/10.5286/ISIS.E.RB1320200

Data is released under the CC-BY-4.0 license.



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