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arXiv · 0804.4781

The symmetry of the spin Hamiltonian in herbertsmithite, a spin-1/2 kagomé lattice

Oren Ofer·Amit Keren
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Abstract

We present magnetization measurements on oriented powder of ZnCu$_{3}$(OH)$_{6}$Cl$_{2}$ along and perpendicular to the orienting field. We find a dramatic difference in the magnetization between the two directions. It is biggest at low measurement fields $H$ or high temperatures. We show that the difference at high temperatures must emerge from Ising-like exchange anisotropy. This allows us to explain muon spin rotation data at $T\to 0$ in terms of an exotic ferromagnetic ground state.

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Oren Ofer, Amit Keren. 2009-04-21. The symmetry of the spin Hamiltonian in herbertsmithite, a spin-1/2 kagomé lattice. https://doi.org/10.1103/physrevb.79.134424

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