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Quantum critical point in CuGeO3 doped with magnetic impurities

S. V. Demishev·Y. Inagaki·M. M. Markina·H. Ohta·S. Okubo·Y. Oshima·A. A. Pronin·N. E. Sluchanko·N. A. Samarin·V. V. Glushkov
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Abstract

Using high frequency (up to 450 GHz) ESR and low temperature specific heat measurements we find that insertion of 1% Fe and 2% Co damps spin-Peierls and Neel transitions and for T<30K gives rise to onset of a quantum critical behaviour characteristic for a random dimer Griffiths phase.

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S. V. Demishev, Y. Inagaki, M. M. Markina, H. Ohta, S. Okubo, Y. Oshima, A. A. Pronin, N. E. Sluchanko, N. A. Samarin, V. V. Glushkov. 2003-01-30. Quantum critical point in CuGeO3 doped with magnetic impurities. https://doi.org/10.1016/s0921-4526(02)02022-7

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