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Dynamical breakdown of the Ising spin-glass order under a magnetic field

P. E. Jönsson·H. Takayama·H. Aruga Katori·A. Ito
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Abstract

The dynamical magnetic properties of an Ising spin glass Fe$_{0.55}$Mn$_{0.45}$TiO$_3$ are studied under various magnetic fields. Having determined the temperature and static field dependent relaxation time $τ(T;H)$ from ac magnetization measurements under a dc bias field by a general method, we first demonstrate that these data provide evidence for a spin-glass (SG) phase transition only in zero field. We next argue that the data $τ(T;H)$ of finite $H$ can be well interpreted by the droplet theory which predicts the absence of a SG phase transition in finite fields.

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P. E. Jönsson, H. Takayama, H. Aruga Katori, A. Ito. 2005-03-14. Dynamical breakdown of the Ising spin-glass order under a magnetic field. https://doi.org/10.1103/physrevb.71.180412

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