1/N Expansion for Critical Exponents of Magnetic Phase Transitions in CP^{N-1} Model at 2<d<4

V. Yu. Irkhin; A. A. Katanin; M. I. Katsnelson

doi:10.1103/physrevb.54.11953

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arXiv · cond-mat/9703011

1/N Expansion for Critical Exponents of Magnetic Phase Transitions in CP^{N-1} Model at 2<d<4

V. Yu. Irkhin·A. A. Katanin·M. I. Katsnelson

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Abstract

Critical exponents in the CP^{N-1} model, which describes localized-moment ferro- and antiferromagnets (N=2 in the Heisenberg model), are calculated from two-particle Green's functions to first order in 1/N. For d=2+εthe results agree with earlier renormalization group calculations. For d=3 the leading 1/N-corrections turn out to be very large at N=2. For d=4-εthe 1/N-corrections are small at any N and insufficient to describe correctly the magnetic phase transition.

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V. Yu. Irkhin, A. A. Katanin, M. I. Katsnelson. 1997-03-02. 1/N Expansion for Critical Exponents of Magnetic Phase Transitions in CP^{N-1} Model at 2<d<4. https://doi.org/10.1103/physrevb.54.11953

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