The suppression of the spin ice state in the mixed B-site pyrochlore Dy₂ScNbO₇.

The pyrochlore oxides (with the chemical formula A₂B₂O₇) have been central to the study of geometric frustration for the past several decades. Pyrochlores in which the A-site is occupied by dysprosium exhibit a spin ice state, a phenomenon that has been well studied in Dy_2Ti2O₇, Dy₂Sn₂O₇, and Dy₂Ge₂O₇. To explore the robustness of the spin ice state in the face of chemical perturbation, we present an investigation of Dy₂ScNbO₇, where the non-magnetic B-site is occupied by a stoichiometric mixture of Sc³⁺ and Nb⁵⁺ cations. Using magnetometry, heat capacity, muon spin relaxation, and inelastic neutron scattering measurements, we show that Dy₂ScNbO₇ does not appear to adopt the spin ice ground state. Experimental results that provide evidence that the B-site disorder appears to destroy the expected Ising anisotropy of the system, which is a crucial ingredient for the spin ice state, will be presented.