Suppression of Pauling's Residual Entropy in Dilute Spin Ice (Dy$_{1-x}$Y$_x$)$_2$Ti$_2$O$_7$

S. Scharffe; O. Breunig; V. Cho; P. Laschitzky; M. Valldor; J. F. Welter; T. Lorenz

doi:10.1103/PhysRevB.92.180405

paper

Suppression of Pauling's Residual Entropy in Dilute Spin Ice (Dy $_{1 - x}$ Y $_{x}$ ) $_{2}$ Ti $_{2}$ O $_{7}$

arXiv:1503.03856 · doi:10.1103/PhysRevB.92.180405

Abstract

Around 0.5 K, the entropy of the spin-ice Dy $_{2}$ Ti $_{2}$ O $_{7}$ has a plateau-like feature close to Pauling's residual entropy derived originally for water ice, but an unambiguous quantification towards lower temperature is prevented by ultra-slow thermal equilibration. Based on specific heat data of (Dy $_{1 - x}$ Y $_{x}$ ) $_{2}$ Ti $_{2}$ O $_{7}$ we analyze the influence of non-magnetic dilution on the low-temperature entropy. With increasing x, the ultra-slow thermal equilibration rapidly vanishes, the low-temperature entropy systematically decreases and its temperature dependence strongly increases. These data suggest that a non-degenerate ground state is realized in (Dy $_{1 - x}$ Y $_{x}$ ) $_{2}$ Ti $_{2}$ O $_{7}$ for intermediate dilution. This contradicts the expected zero-temperature residual entropy obtained from a generalization of Pauling's theory for dilute spin ice, but is supported by Monte Carlo simulations.

5 pages, 4 figures; slightly revised version to appear in PRB Rapid Communications

Suppression of Pauling's Residual Entropy in Dilute Spin Ice (Dy $_{1 - x}$ Y $_{x}$ ) $_{2}$ Ti $_{2}$ O $_{7}$

Abstract

References in corpus (7)

Cited by in corpus (5)

Suppression of Pauling's Residual Entropy in Dilute Spin Ice (Dy1−x​Yx​)2​Ti2​O7​

Abstract

References in corpus (7)

Cited by in corpus (5)

Suppression of Pauling's Residual Entropy in Dilute Spin Ice (Dy $_{1 - x}$ Y $_{x}$ ) $_{2}$ Ti $_{2}$ O $_{7}$