Magnetic susceptibility and specific heat studies on heavy rare earth ruthenate pyrochlores R2Ru2O7(R = Gd–Yb)

Magnetic susceptibility and specific heat measurements were performed for heavy rare earth ruthenate pyrochlores R2Ru2O7 (R = Gd, Tb, Dy, Ho, Er, Tm, and Yb). The compounds of R = Tb, Er, and Yb show magnetic transitions at 3.4, 5.4, and 6.3 K, respectively, in the magnetic susceptibility vs. temperature curves. λ-Type anomalies indicating long-range magnetic ordering are observed in the specific heat vs. temperature curves for all of the compounds. At very low temperatures, the presence of short-range magnetic interactions between the rare earth ions for R = Tb, Er, and Yb compounds is indicated from both the susceptibility and the specific heat data.

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