title: Fluctuation-driven quantum phase transitions in clean itinerant ferromagnets.
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< or =3. A renormalized mean-field theory predicts a fluctuation-induced first order transition for 1<d< or =3, whose stability is analyzed by renormalization group techniques. Depending on microscopic parameter values, the first order transition can be stable, or be preempted by a fluctuation-induced second order transition. The critical behavior at the latter is determined. The results are in agreement with recent experiments.
authors.affiliation: Department of Physics, and Materials Science Institute, University of Oregon, Eugene 97403, USA.
authors.forename: D
authors.initials: D
authors.lastname: Belitz
authors.forename: T R
authors.initials: TR
authors.lastname: Kirkpatrick