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arXiv · 1704.07776

Magnetic Field Dependence of Spin Glass Free Energy Barriers

Samaresh Guchhait·Raymond L. Orbach
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Abstract

We measure the field dependence of spin glass free energy barriers in a thin amorphous Ge:Mn film through the time dependence of the magnetization. After the correlation length $ξ(t, T)$ has reached the film thickness $\mathcal {L}=155$~Å~so that the dynamics are activated, we change the initial magnetic field by $δH$. In agreement with the scaling behavior exhibited in a companion Letter [Janus collaboration: M. Baity-Jesi {\it et al.}, Phys. Rev. Lett. {\bf 118}, 157202 (2017)], we find the activation energy is increased when $δH < 0$. The change is proportional to $(δH)^2$ with the addition of a small $(δH)^4$ term. The magnitude of the change of the spin glass free energy barriers is in near quantitative agreement with the prediction of a barrier model.

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Samaresh Guchhait, Raymond L. Orbach. 2017-04-25. Magnetic Field Dependence of Spin Glass Free Energy Barriers. https://doi.org/10.1103/physrevlett.118.157203

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