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Ferromagnetic Transition in One-Dimensional Itinerant Electron Systems

Kun Yang
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Abstract

We use bosonization to derive the effective field theory that properly describes ferromagnetic transition in one-dimensional itinerant electron systems. The resultant theory is shown to have dynamical exponent z=2 at tree leve and upper critical dimension d_c=2. Thus one dimension is below the upper critical dimension of the theory, and the critical behavior of the transition is controlled by an interacting fixed point, which we study via epsilon expansion. Comparisons will be made with the Hertz-Millis theory, which describes the ferromagnetic transition in higher dimensions.

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Kun Yang. 2004-08-04. Ferromagnetic Transition in One-Dimensional Itinerant Electron Systems. https://doi.org/10.1103/physrevlett.93.066401

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