J. Phys. Soc. Jpn. 71 (2002) pp. 2365-2368 |Next Article| |Table of Contents|
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Exact Result of Ground-State Entropy for Ising Pyrochlore Magnets under a Magnetic Field along  Axis
Department of Physics, University of Tokyo, Hongo, Tokyo 113-0033 1Institute for Solid State Physics, University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8581
(Received June 12, 2002)
Ground-state entropy for an Ising pyrochlore lattice is calculated exactly under a certain range of magnetic field along the  axis, where the ground-state entropy shows a plateau. The obtained entropy is 0.0808kB per spin, which agrees with the experimental value. Pauling's method for estimating the ground-state entropy for the ice problem is also applied to the present case. Comparison of the result obtained with our exact result shows that Pauling's method underestimates the entropy by about 10%.
©2002 The Physical Society of Japan
KEYWORDS:pyrochlore, frustration, ground-state entropy, dimer-covering problem, kagomé lattice
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