muSR study of the novel magnetism and spin dynamics in a new dilute magnetic semiconductor series

Dilute ferromagnetism in insulative semiconductors, wherein only a small amount (~1-3%) of magnetic ions are doped, has received severe arguments toward its intrinsic nature since its first report in 1991 because no concrete evidence has been obtained via reliable experimental techniques such as muSR or neutron diffraction. However, we recently found intrinsic dilute ferromagnetism in luminescent semiconductors SrSiO3 (SSO). Our latest ISIS experiment, RB2510182 (muSR study of the percolation process in a new dilute magnetic semiconductor series), on scarcely diluted samples of 1%, 0.1%, and 0.014%Dy:SSO has successfully revealed that the long-range order can be established at Dy/Sr = 0.1%, and the internal field in the 0.014%Dy:SSO shows a prominent dynamic nature. We have further found contrasting magnetization characteristics for 5%Dy:SSO, 5%Ho:SSO, 5%Eu:SSO, 5%Tb:SSO etc., implying different spin dynamics in them. In particular, our new neutron experiments show long-range ferromagnetic order for 5%Dy:SSO but short-ranged one for 5%Ho:SSO. Therefore, it is of great interest to investigate and compare the dynamics in this system doped with these different ions. The investigation and verification of the predicted contrastingly different dynamics for these different magnetic ions would produce fruitful results and enrich this novel work on the intrinsic dilute magnetism.