Magnetic properties of strongly frustrated magnet, SrCr9(Ga–In)3O19

Abstract To investigate the anomalous magnetic properties of SrCr 9− x Ga 3+ x O 19 , SrCr 9− x (Ga 0.95 In 0.05 ) 3+ x O 19 compounds were synthesized including the x =0 compound. Magnetic and μSR measurements give results in good agreement with the reported results indicating an insignificant role of the defects in the magnetic Cr lattice. Based on the results, the plaquette ordering model is presented. Below 60 K, seven moments on a bitetrahedron plaquette exhibit order to give one moment. The surviving moments do not order due to frustration but are frozen below T f . The muoniums formed in the compound combine with the oxygen ions and experience transferred hyperfine fields from Cr moments. This field is shielded by the electron of the muonium to be hardly decoupled by the external field.