Magnetothermal study of Dy Stuffed Spin Ice: Dy2(DyxTi2-x)O7-x/2
  We have studied the thermodynamics of the stuffed spin ice material, Dy2(DyxTi2-x)O7-x/2, in which additional Dy3+ replace Ti4+ in the pyrochlore Dy2Ti2O7. Heat capacity measurements indicate that these materials lose the spin ice zero point entropy for x >= 0.3, sharply contrasting with results on the analogous Ho materials. A finite ac susceptibility is observed as T ~ 0 in both the Ho and Dy materials with x = 0.67, which suggests that spin fluctuations persist down to T ~ 0. We propose that both the entropy and susceptibility data may be explained as a result of domains of local pyrochlore type structural order in these materials. 
B. G. Ueland, G. C. Lau, R.S. Freitas, J. Snyder, M. L. Dahlberg, B.   D. Muegge, E. L. Duncan, R. J. Cava, and P. Schiffer