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Quantum critical behavior of disordered itinerant ferromagnets

T. R. Kirkpatrick·D. Belitz
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Abstract

The quantum ferromagnetic transition at zero temperature in disordered itinerant electron systems is considered. Nonmagnetic quenched disorder leads to diffusive electron dynamics that induces an effective long-range interaction between the spin or order parameter fluctuations of the form r^{2-2d}, with d the spatial dimension. This leads to unusual scaling behavior at the quantum critical point, which is determined exactly. In three-dimensional systems the quantum critical exponents are substantially different from their finite temperature counterparts, a difference that should be easily observable. Experiments to check these predictions are proposed.

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BibTeXRIS

T. R. Kirkpatrick, D. Belitz. 1997-03-19. Quantum critical behavior of disordered itinerant ferromagnets. https://doi.org/10.1103/physrevb.53.14364

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