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.
@article{arxiv.cond-mat/0211326,
title = {Specific Heat of Kagome Ice in the Pyrochlore Oxide Dy2Ti2O7},
author = {Z. Hiroi and K. Matsuhira and S. Takagi and T. Tayama and T. Sakakibara},
journal= {arXiv preprint arXiv:cond-mat/0211326},
year = {2009}
}
Comments
9 pages, 14 figures, J. Phys. Soc. Jpn, Vol. 72, in press