Annalen Der Physik Critical and Oo-critical Singularities in Disordered Quantum Magnets
نویسنده
چکیده
We study disordered systems at and near quantum phase transitions, which are transitions at zero temperature that are driven by quantum instead of thermal uctu-ations. Special emphasis is put on the so-called Griiths-McCoy regions surrounding these transitions in magnetic systems, where various susceptibilities are found to be divergent for T ! 0 without the system being critical. We present a phenomenological picture for uncor-related and weakly or strongly correlated disorder and check it for various models. In higher dimensions the phenomena seem to be connected to a percolation transition.
منابع مشابه
Critical and oÿ-critical singularities in disordered quantum magnets
We study disordered systems at and near quantum phase transitions, which are transitions at zero temperature that are driven by quantum instead of thermal ÿuctuations. Special emphasis is put on the so-called Griþths-McCoy regions surrounding these transitions in magnetic systems, where various susceptibilities are found to be divergent for T ! 0 without the system being critical. We present a ...
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