Ground state of the spin-1/2 chain of green dioptase at high fields

Kazuki Matsui; Masashi Fujisawa; Kenta Hagiwara; Yukihiro Hoshino; Takayuki Goto; Takahiko Sasaki; Hidekazu Tanaka; Susumu Okubo; Hitoshi Ohta

arXiv · 1309.5472

Ground state of the spin-1/2 chain of green dioptase at high fields

Kazuki Matsui·Masashi Fujisawa·Kenta Hagiwara·Yukihiro Hoshino·Takayuki Goto·Takahiko Sasaki·Hidekazu Tanaka·Susumu Okubo·Hitoshi Ohta

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Abstract

The gem-stone dioptase Cu6Si6O18.6H2O has a chiral crystal structure of equilateral triangular helices consisting of Cu-3d spins. It shows an antiferromagnetic order with an easy axis along c at TN = 15.5 K under zero field, and a magnetization jump at HC = 13.5 T when the field is applied along c-axis. By 29Si-NMR measurements, we have revealed that the high-field state is essentially the two sub-lattice structure, and that the component within ab-plane is collinear. The result indicates no apparent match with the geometrical pattern of helical spin chain.

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Kazuki Matsui, Masashi Fujisawa, Kenta Hagiwara, Yukihiro Hoshino, Takayuki Goto, Takahiko Sasaki, Hidekazu Tanaka, Susumu Okubo, Hitoshi Ohta. 2013-10-08. Ground state of the spin-1/2 chain of green dioptase at high fields. https://arxiv.org/abs/1309.5472

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