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Ising Spin Glass in a Transverse Magnetic Field

Beatriz Boechat·Raimundo R. dos Santos·M. A. Continentino
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Abstract

We study the three-dimensional quantum Ising spin glass in a transverse magnetic field following the evolution of the bond probability distribution under Renormalisation Group transformations. The phase diagram (critical temperature $T_c$ {\em vs} transverse field $Γ$) we obtain shows a finite slope near $T=0$, in contrast with the infinite slope for the pure case. Our results compare very well with the experimental data recently obtained for the dipolar Ising spin glass LiHo$_{0.167}$Y$_{0.833}$F$_4$, in a transverse field. This indicates that this system is more apropriately described by a model with short range interactions than by an equivalent Sherrington-Kirkpatrick model in a transverse field.

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Beatriz Boechat, Raimundo R. dos Santos, M. A. Continentino. 1993-12-08. Ising Spin Glass in a Transverse Magnetic Field. https://doi.org/10.1103/physrevb.49.6404

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