Magnetic interactions in the room-temperature skyrmion material Co8Zn8Mn4

We propose an investigation of the spin-waves in the recently discovered room-temperature skyrmion material Co8Zn8Mn4. The ground state of Co8Zn8Mn4 is a very long wavelength helix of wavelength 125 nm as shown by previous SANS measurements, and application of a magnetic field of between 100 and 500 G at T~ 290 K stabilises a skyrmion lattice phase. Recent studies show that this skyrmion lattice is remarkably robust as a function of temperature, and is metastable on field-cooling down to zero temperature. This makes Co8Zn8Mn8 a technologically interesting material, and understanding of the fundamental interactions is important. We will perform Horace scans on MERLIN in RRM mode to cover a wide range of energy scales, and will need 4 days beamtime to complete this measurement.