Decay of spin-Peierls state in CuGeO3:Fe. The case of a strong disorder

S. V. Demishev; R. V. Bunting; A. A. Pronin; N. E. Sluchanko; N. A. Samarin; H. Ohta; S. Okubo; Y. Oshima; L. I. Leonyuk; M. M. Markina

arXiv · cond-mat/0110177

Decay of spin-Peierls state in CuGeO3:Fe. The case of a strong disorder

S. V. Demishev·R. V. Bunting·A. A. Pronin·N. E. Sluchanko·N. A. Samarin·H. Ohta·S. Okubo·Y. Oshima·L. I. Leonyuk·M. M. Markina

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Abstract

Influence of doping by iron impurity on spin-Peierls state in CuGeO3 is studied. ESR measurements for the frequency/temperature domain 60-450 GHz/ 1.8-300 K and specific heat data obtained for the interval 6-20 K show that insertion of 1% of Fe completely destroy both spin-Peierls and antiferromagnetic orders. Damping of long-range magnetic order is accompanied by onset at T<20 K of power asymptotics for magnetic susceptibility chi~T^-alpha and magnetic part of specific heat cm~T^(1-alpha), with the index alpha=0.35-0.37. This effect is characteristic to the limit of strong disorder for doped CuGeO3 and may reflect formation of the Griffiths phase at low temperatures in CuGeO3:Fe.

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S. V. Demishev, R. V. Bunting, A. A. Pronin, N. E. Sluchanko, N. A. Samarin, H. Ohta, S. Okubo, Y. Oshima, L. I. Leonyuk, M. M. Markina. 2001-10-09. Decay of spin-Peierls state in CuGeO3:Fe. The case of a strong disorder. https://arxiv.org/abs/cond-mat/0110177

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