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External field dependence of the correlation lengths in the three-dimensional O(4) model

J. Engels·L. Fromme·M. Seniuch
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Abstract

We investigate numerically the transverse and longitudinal correlation lengths of the three-dimensional O(4) model as a function of the external field H. In the low-temperature phase we verify explicitly the H^{-1/2}-dependence of the transverse correlation length, which is expected due to the Goldstone modes of the model. On the critical line we find the universal amplitude ratio xi^c_T / xi^c_L = 1.99(1). From our data we derive the universal scaling function for the transverse correlation length. The H-dependencies of the correlation lengths in the high temperature phase are discussed and shown to be in accord with the scaling functions.

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J. Engels, L. Fromme, M. Seniuch. 2003-09-01. External field dependence of the correlation lengths in the three-dimensional O(4) model. https://doi.org/10.1016/s0920-5632(03)02712-9

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