EuSe is a simple magnetic system that appears to show many complicated features. Under applied pressure it undergoes a transition from an antiferromagnet (AF) to a ferromagnet (FM). This transition provides a means of testing certain basic fundamentals of magnetic theory and an opportunity to explore the complexities of EuSe. Using the muon-spin rotation and relaxation technique (μSR), EuSe was measured at pressures ranging from ambient to 11 kbar. In ambient-pressure EuSe, muon data reveal two local fields, but show only a single field in the FM state formed under pressure. The μSR measurements appear to show a continuous transition at Tc, contrary to previous Mössbauer results that were interpreted as being evidence of a first-order transition. Values determined for the critical exponent, β, in AF and FM EuSe, differ and therefore appear to be a clear counterexample to the Universality Hypothesis. The values of β also are indicative of EuSe's being a 2D magnet for pressures up to 11 kbar. The nature and values of the local fields seen by the muons is discussed and analyzed.
Publication Source (Journal or Book title)
Terry, I., Adams, P., Bykovetz, N., Giblin, S., Guguchi, Z., Khasanov, R., Klein, J., Lin, C., & Liu, T. (2016). An exploration of some magnetic fundamentals in EuSe using μSR. AIP Advances, 6 (5) https://doi.org/10.1063/1.4943235