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Mapping the critical region along the second-order chiral phase boundary

Shi Yin*

  • *Contact author: shiyin.dalian@gmail.com
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Phys. Rev. D 114, 034027 – Published 12 August, 2026

DOI: https://doi.org/10.1103/wtzd-jjwx

Abstract

We investigate the extent of the critical scaling region of the chiral phase transition at finite chemical potential within the quark-meson model using the functional renormalization group approach. By analyzing the scaling behavior of the chiral order parameter and correlation length with respect to temperature and pion mass near the second-order phase transition, we extract critical exponents from the data and quantify the range over which the scaling relations remain valid. We find that both the leading-order and the next-to-leading-order scaling regions systematically shrink as the chemical potential increases. This behavior is observed in both the local potential approximation (LPA) and its extension including anomalous dimensions (LPA′), with qualitatively consistent results, while the scaling region in LPA′ is slightly smaller than that in LPA.

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Phys. Rev. D 114, 034027– Published 12 August, 2026
  • Received 24 March 2026
  • Accepted 29 July 2026
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