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Quantum phase transition in the dioptase magnetic lattice

C. Gros·P. Lemmens·K. -Y. Choi·G. G"untherodt·M. Baenitz·H. H. Otto
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Abstract

The study of quantum phase transitions, which are zero-temperature phase transitions between distinct states of matter, is of current interest in research since it allows for a description of low-temperature properties based on universal relations. Here we show that the crystal green dioptase Cu_6Si_6O_18 . 6H_2O, known to the ancient Roman as the gem of Venus, has a magnetic crystal structure, formed by the Cu(II) ions, which allows for a quantum phase transition between an antiferromagnetically ordered state and a quantum spin liquid.

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C. Gros, P. Lemmens, K. -Y. Choi, G. G"untherodt, M. Baenitz, H. H. Otto. 2002-08-06. Quantum phase transition in the dioptase magnetic lattice. https://doi.org/10.1209/epl%2Fi2002-00347-0

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