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

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

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

Authors

Description

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.
Submitted to NanoRes-2004, Kazan, Russia, Aug. 15-19, 2004