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Long-range order versus random-singlet phases in quantum antiferromagnetic systems with quenched disorder

T. R. Kirkpatrick·D. Belitz
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Abstract

The stability of antiferromagnetic long-range order against quenched disorder is considered. A simple model of an antiferromagnet with a spatially varying Neel temperature is shown to possess a nontrivial fixed point corresponding to long-range order that is stable unless either the order parameter or the spatial dimensionality exceeds a critical value. The instability of this fixed point corresponds to the system entering a random-singlet phase. The stabilization of long-range order is due to quantum fluctuations, whose role in determining the phase diagram is discussed.

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BibTeXRIS

T. R. Kirkpatrick, D. Belitz. 1997-04-10. Long-range order versus random-singlet phases in quantum antiferromagnetic systems with quenched disorder. https://doi.org/10.1103/physrevlett.76.2571

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