Scaling of Memories and Crossover in Glassy Magnets

A. M. Samarakoon; M. Takahashi; D. Zhang; J. Yang; N. Katayama; R. Sinclair; H. D. Zhou; S. O. Diallo; G. Ehlers; D. A. Tennant; S. Wakimoto; K. Yamada; G-W. Chern; T. J. Sato; S. -H. Lee

arXiv · 1708.07974

Scaling of Memories and Crossover in Glassy Magnets

A. M. Samarakoon·M. Takahashi·D. Zhang·J. Yang·N. Katayama·R. Sinclair·H. D. Zhou·S. O. Diallo·G. Ehlers·D. A. Tennant·S. Wakimoto·K. Yamada·G-W. Chern·T. J. Sato·S. -H. Lee

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Abstract

Glassiness is ubiquitous and diverse in characteristics in nature. Understanding their differences and classification remains a major scientific challenge. Here, we show that scaling of magnetic memories with time can be used to classify magnetic glassy materials into two distinct classes. The systems studied are high-temperature superconductor-related materials, spin-orbit Mott insulators, frustrated magnets, and dilute magnetic alloys. Our bulk magnetization measurements reveal that most densely populated magnets exhibit similar memory behavior characterized by a relaxation exponent of 1-n ~ 0.6(1). This exponent is different from 1-n ~ 1/3 of dilute magnetic alloys that was ascribed to their hierarchical and fractal energy landscape and is also different from 1-n=1 of the conventional Debye relaxation expected for a spin solid, a state with long range order. Furthermore, our systematic study on dilute magnetic alloys with varying magnetic concentration exhibits crossovers among the two glassy states and spin solid.

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A. M. Samarakoon, M. Takahashi, D. Zhang, J. Yang, N. Katayama, R. Sinclair, H. D. Zhou, S. O. Diallo, G. Ehlers, D. A. Tennant, S. Wakimoto, K. Yamada, G-W. Chern, T. J. Sato, S. -H. Lee. 2017-08-26. Scaling of Memories and Crossover in Glassy Magnets. https://arxiv.org/abs/1708.07974

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