Fluctuation-Driven Quantum Phase Transitions in Clean Itinerant Ferromagnets

D. Belitz; T. R. Kirkpatrick

doi:10.1103/physrevlett.89.247202

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Fluctuation-Driven Quantum Phase Transitions in Clean Itinerant Ferromagnets

D. Belitz·T. R. Kirkpatrick

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Abstract

The quantum phase transition in clean itinerant ferromagnets is analyzed. It is shown that soft particle-hole modes invalidate Hertz's mean-field theory for $d \leq 3$. A renormalized mean-field theory predicts a fluctuation-induced first order transition for $1 < d \leq 3$, whose stability is analyzed by renormalization group techniques. Depending on microscopic parameter values, the first order transition can be stable, or be pre-empted by a fluctuation-induced second order transition. The critical behavior at the latter is determined. The results are in agreement with recent experiments.

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BibTeX RIS

D. Belitz, T. R. Kirkpatrick. 2003-07-17. Fluctuation-Driven Quantum Phase Transitions in Clean Itinerant Ferromagnets. https://doi.org/10.1103/physrevlett.89.247202

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