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arXiv · 1110.3889

Experimental Realization of Spin-1/2 Triangular-Lattice Heisenberg Antiferromagnet

Yutaka Shirata·Hidekazu Tanaka·Akira Matsuo·Koichi Kindo
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Abstract

We report the results of magnetization and specific heat measurements on Ba$_3$CoSb$_2$O$_9$, in which the magnetic Co$^{2+}$ ion has a fictitious spin-1/2, and show evidence that a spin-1/2 Heisenberg antiferromagnet on a regular triangular lattice is actually realized in Ba$_3$CoSb$_2$O$_9$. We found that the entire magnetization curve including the one-third quantum magnetization plateau is in excellent agreement with theoretical calculations at a quantitative level.

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Yutaka Shirata, Hidekazu Tanaka, Akira Matsuo, Koichi Kindo. 2011-10-18. Experimental Realization of Spin-1/2 Triangular-Lattice Heisenberg Antiferromagnet. https://doi.org/10.1103/physrevlett.108.057205

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