Hot Defect Superconformal Field Theory in an External Magnetic Field

In this paper we investigate the influence of an external magnetic field on a flavored holographic gauge theory dual to the D3/D5-brane intersection at finite temperature. Our study shows that the external magnetic field has a freezing effect on the meson melting phase transition. We construct the corresponding phase diagram. We investigate some thermodynamic quantities of the theory. A study of the entropy density reveals enhanced relative jump of the entropy density at the ``chiral" phase transition. A study of the magnetization shows that both the confined and deconfined phases exhibit diamagnetic response. The diamagnetic response in the deconfined phase has a stronger temperature dependence reflecting the temperature dependence of the conductivity. We study the meson spectrum of the theory and analyze the stability of the different phases by looking at both normal and quasinormal semi-classical excitations. For the symmetry breaking phase we analyze the corresponding pseudo-Goldstone modes and prove that they satisfy non-relativistic dispersion relation.