Single ion anisotropy of Kagome spin ice HoAgGe and DyAgGe by inelastic neutron scattering

Spin ices are exotic phases of matter characterized by frustrated spins obeying local “ice rules” that minimize the number of spatially isolated magnetic monopoles, in analogy with the electric dipoles in water ice. HoAgGe, as one example of the ReAgGe system, attracted much attention as the first discovery of Kagome Spin Ice in the intermetallic system. Alternating clockwise and counter-clockwise order was founded at base temperature. The behavior of Kagome Spin Ice is strongly influenced by the single-ion anisotropy properties, which are determined by the crystal electric field (CEF) ground state. We propose utilizing the MARI instrument to investigate the crystal field excitations of HoAgGe and DyAgGe, utilizing 3g non-aligned single crystals samples (in powder form), which will allow to fit the observed CEF excitations using the Mantid CEF program. We estimate 3 days of beam time to complete the proposed measurements on three samples.