Crystalline-electric-field excitations of an Yb-based kagome lattice Kondo antiferromagnet

Materials where the magnetic ions form a kagome lattice often exhibit magnetic frustration, meaning that no ground state satisfies all the magnetic interactions, leading to novel electronic phases. The outcome when strong frustration is paired with strong hybridization effects (Kondo coupling) in Yb-based heavy fermion systems remains to be determined. Here we propose to perform inelastic neutron scattering on powder samples of the recently identified kagome lattice Kondo antiferromagnet YbPdAs using the MERLIN spectrometer, so as to probe the crystalline-electric-fields (CEF) excitations and determine the CEF level scheme and ground state 4f-wave function. This will provide important information about the magnetic anisotropy, enabling a microscopic understanding of the frustration, as well as the degree of Kondo hybridization.