First order transitions and multicritical points in weak itinerant ferromagnets

D. Belitz; T. R. Kirkpatrick; Thomas Vojta

doi:10.1103/physrevlett.82.4707

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First order transitions and multicritical points in weak itinerant ferromagnets

D. Belitz·T. R. Kirkpatrick·Thomas Vojta

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Abstract

It is shown that the phase transition in low-T_c clean itinerant ferromagnets is generically of first order, due to correlation effects that lead to a nonanalytic term in the free energy. A tricritical point separates the line of first order transitions from Heisenberg critical behavior at higher temperatures. Sufficiently strong quenched disorder suppresses the first order transition via the appearance of a critical endpoint. A semi-quantitative discussion is given in terms of recent experiments on MnSi, and predictions for other experiments are made.

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D. Belitz, T. R. Kirkpatrick, Thomas Vojta. 1999-08-31. First order transitions and multicritical points in weak itinerant ferromagnets. https://doi.org/10.1103/physrevlett.82.4707

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