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Quantum Critiality and Collective Effects in Low Dimensional Magnet CuGeO3 Probed by High Frequency EPR

S. V Demishev·A. V. Semeno·A. A. Pronin·N. E. Sluchanko·N. A. Samarin·H. Ohta·S. Okubo·M. Kimata·K. Koyama·M. Motokawa·A. V. Kuznetsov
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Abstract

For the CuGeO3 single crystals doped with 1% of Fe the quantum critical behavior in a wide temperature range 1-40 K is reported. The critical exponents for susceptibility along different crystallographic axes are determined: a=0.34 (B //a and B //c) and a=0.31 (B //b). The description of the temperature dependences of the line width and g-factor could be obtained in the OA theory assuming that staggered component of the magnetic moment is located predominantly along b axis. Possible arguments favoring the competition between effects of the staggered field and antiferromagnetic ordering are provided.

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S. V Demishev, A. V. Semeno, A. A. Pronin, N. E. Sluchanko, N. A. Samarin, H. Ohta, S. Okubo, M. Kimata, K. Koyama, M. Motokawa, A. V. Kuznetsov. 2004-08-11. Quantum Critiality and Collective Effects in Low Dimensional Magnet CuGeO3 Probed by High Frequency EPR. https://arxiv.org/abs/cond-mat/0408242

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