Exploring QCD phase transitions and neutron star properties via holographic models

We investigate the QCD phase transition and its phase structure within Einstein–Maxwell-Dilaton-scalar system and compare the results with those obtained from the Einstein–Maxwell-Dilaton system. It is shown that both models reproduce behavior consistent with lattice QCD. In particular, the Einstein–Maxwell-Dilaton-scalar system exhibits a first-order phase transition in the pure gauge sector, aligning with predictions from Yang–Mills theory. Based on these models, we construct a holographic model for neutron stars, incorporating leptons to satisfy electric charge neutrality, and examine the cold equation of state, the mass-radius relation, and tidal deformability of neutron stars. It is demonstrated that the Einstein–Maxwell-Dilaton-scalar system enables us to describe neutron star properties that meet current astrophysical constraints.