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Specific Heat of Kagome Ice in the Pyrochlore Oxide Dy2Ti2O7

Z. Hiroi·K. Matsuhira·S. Takagi·T. Tayama·T. Sakakibara
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Abstract

A novel macroscopically degenerate state called kagome ice, which was recently found in a spin ice compound Dy2Ti2O7 in a magnetic field applied along the [111] direction of the cubic unit cell, is studied by specific heat measurements. The residual entropy of the kagome ice is estimated to be 0.65 J/K mol Dy, which is nearly 40 % of that for the tetrahedral spin ice obtained in a zero field (1.68 J/K mol Dy) and is in good agreement with a theoretical prediction. It is also reported that the kagom ice state, which is stabilized at a range of magnetic field of 0.3 ~ 0.6 T, is a 'gas' phase and condenses into a 'liquid' phase with nearly zero entropy at a critical field of 1 T.

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Z. Hiroi, K. Matsuhira, S. Takagi, T. Tayama, T. Sakakibara. 2002-11-15. Specific Heat of Kagome Ice in the Pyrochlore Oxide Dy2Ti2O7. https://doi.org/10.1143/jpsj.72.411

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