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Breakdown of Landau-Ginzburg-Wilson theory for certain quantum phase transitions

T. Vojta·D. Belitz·R. Narayanan·T. R. Kirkpatrick
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Abstract

The quantum ferromagnetic transition of itinerant electrons is considered. It is shown that the Landau-Ginzburg-Wilson theory described by Hertz and others breaks down due to a singular coupling between fluctuations of the conserved order parameter. This coupling induces an effective long-range interaction between the spins of the form 1/r^{2d-1}. It leads to unusual scaling behavior at the quantum critical point in $1<d\leq 3$ dimensions, which is determined exactly.

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T. Vojta, D. Belitz, R. Narayanan, T. R. Kirkpatrick. 1997-04-10. Breakdown of Landau-Ginzburg-Wilson theory for certain quantum phase transitions. https://doi.org/10.1209/epl%2Fi1996-00208-x

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