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arXiv · 1506.03585

Investigations of the effect of nonmagnetic Ca substitution for magnetic Dy on spin-freezing in Dy2Ti2O7

V. K. Anand·D. A. Tennant·B. Lake
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Abstract

Physical properties of partially Ca substituted hole-doped Dy2Ti2O7 have been investigated by ac magnetic susceptibility \chi_ac(T), dc magnetic susceptibility \chi(T), isothermal magnetization M(H) and heat capacity C_p(T) measurements on Dy1.8Ca0.2Ti2O7. The spin-ice system Dy2Ti2O7 exhibits a spin-glass type freezing behavior near 16 K. Our frequency dependent \chi_ac(T) data of Dy1.8Ca0.2Ti2O7 show that the spin-freezing behavior is significantly influenced by Ca substitution. The effect of partial nonmagnetic Ca2+ substitution for magnetic Dy3+ is similar to the previous study on nonmagnetic isovalent Y3+ substituted Dy2-xYxTi2O7 (for low levels of dilution), however the suppression of spin-freezing behavior is substantially stronger for Ca than Y. The Cole-Cole plot analysis reveals semicircular character and a single relaxation mode in Dy1.8Ca0.2Ti2O7 as for Dy2Ti2O7. No noticeable change in the insulating behavior of Dy2Ti2O7 results from the holes produced by 10% Ca2+ substitution for Dy3+ ions.

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V. K. Anand, D. A. Tennant, B. Lake. 2015-06-11. Investigations of the effect of nonmagnetic Ca substitution for magnetic Dy on spin-freezing in Dy2Ti2O7. https://doi.org/10.1088/0953-8984/27/43/436001

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