Doped-Hole Dependence on Spin Dynamics in Magnetically Ordered States of (Nd1-xCax)2Ru2O7 Studied by LF-muSR

We proposed to investigate (Nd1-xCax)2Ru2O7 system by using LF-muSR. From previous beam time, we obtained that there is fluctuating internal field at the muon site and the spin dynamics still remain around 30 K for x=0 sample showed by the dip in temperature dependence of relaxation rate which doesn't occur in the x = 0.3 sample. This change indicates that the spin dynamics would be affected by the hole doping. Recently the spin-phonon coupling behavior is discussed in some pyrochlore systems and we expect this effect might be occur in our system. We are going to repeat the LF dependence measurement of relaxation rate around 30 K and obtain changes in the fluctuation frequency of the internal field. We plan to measure the same sequence on x=0.15, 0.30 and 0.40 in order to see changes in TN and the anomaly at 30 K against the hole concentration. We request 5 days beam for this proposal.