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Chiral paramagnetic skyrmion-like phase in MnSi.
C Pappas1, E Lelièvre-Berna, P Falus
1Helmholtz Zentrum Berlin für Materialien und Energie, Glienickerstrasse 100, 14109 Berlin, Germany. pappas@helmholtz-berlin.de
Physical Review Letters
|June 13, 2009
Summary
Researchers discovered a disordered chiral phase in the helimagnet MnSi, potentially a spontaneous Skyrmion phase. This phase exists briefly above the helical transition temperature.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- The helimagnet manganese silicon (MnSi) exhibits complex magnetic phases.
- Understanding chiral fluctuations is crucial for magnetic materials research.
Purpose of the Study:
- To investigate chiral fluctuations in MnSi using advanced neutron scattering techniques.
- To identify and characterize a novel disordered magnetic phase.
Main Methods:
- Polarized neutron scattering
- Neutron spin echo spectroscopy
Main Results:
- Evidence for a completely left-handed and dynamically disordered phase in MnSi.
- This phase appears in a narrow temperature range above the helical transition.
- The disordered phase coexists with the helical phase at the transition temperature.
Conclusions:
- The observed phase is consistent with a spontaneous Skyrmion phase.
- This finding provides new insights into the nature of chiral magnetism and Skyrmion formation.
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