Absence of Conventional Spin-Glass Transition in the Ising Dipolar System LiHo_xY_{1-x}F_4

P. E. Jönsson; R. Mathieu; W. Wernsdorfer; A. M. Tkachuk; B. Barbara

doi:10.1103/physrevlett.98.256403

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arXiv · 0705.0434

Absence of Conventional Spin-Glass Transition in the Ising Dipolar System LiHo_xY_{1-x}F_4

P. E. Jönsson·R. Mathieu·W. Wernsdorfer·A. M. Tkachuk·B. Barbara

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Abstract

The magnetic properties of single crystals of LiHo_xY_{1-x}F_4 with x=16.5% and x=4.5% were recorded down to 35 mK using a micro-SQUID magnetometer. While this system is considered as the archetypal quantum spin glass, the detailed analysis of our magnetization data indicates the absence of a phase transition, not only in a transverse applied magnetic field, but also without field. A zero-Kelvin phase transition is also unlikely, as the magnetization seems to follow a non-critical exponential dependence on the temperature. Our analysis thus unmasks the true, short-ranged nature of the magnetic properties of the LiHo_xY_{1-x}F_4 system, validating recent theoretical investigations suggesting the lack of phase transition in this system.

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P. E. Jönsson, R. Mathieu, W. Wernsdorfer, A. M. Tkachuk, B. Barbara. 2007-06-23. Absence of Conventional Spin-Glass Transition in the Ising Dipolar System LiHo_xY_{1-x}F_4. https://doi.org/10.1103/physrevlett.98.256403

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