Magnetic catalysis and inverse magnetic catalysis in ( 2+1 )-dimensional gauge theories from holographic models

Abstract

We study the deconfinement phase transition in (2 þ 1)-dimensional holographic SUðNÞ gauge theories in the presence of an external magnetic field from the holographic hard and soft wall models. We obtain exact solutions for the critical temperature of the deconfinement transition for any range of magnetic field. As a consequence, we find a critical magnetic field ðB c Þ, in which the critical temperature ðT c Þ vanishes; for B < B c we have an inverse magnetic catalysis and for B > B c we have a magnetic catalysis.

Anisotropic string tensions and inversely magnetic catalyzed deconfinement from a dynamical AdS/QCD model

“…In recent years, the effect of a background magnetic field on the chiral condensate and deconfinement transition has also been discussed holographically. This question has been addressed in both top-down as well as bottom-up models of holographic QCD [46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64]. The top-down models, -unfortunately, not entirely appropriate to describe QCD-like physics in the first place, but more satisfactory as far as the correctness and validness of the duality is concerned-predict magnetic catalysis [46].…”

“…Moreover, these phenomenological bottom-up models do not always solve the gravity equations explicitly and in most cases the running of the coupling constant (or the dual dilaton field) is introduced by hand in an ad hoc way into the Einstein-Hilbert action. In 2 + 1 dimensions, sensible solutions displaying inverse magnetic catalysis have been found in [57][58][59], while in 3+1, [61,62] displayed the possibility of inverse catalysis, depending on the value of a new parameter c which can influence AdS/QCD at vanishing magnetic field as well.…”

Melting holographic mesons by applying a magnetic field

“…IMC for the confinement/deconfinement transition has been studied using holographic methods in [12,13], while IMC for chiral symmetry restauration has been reported to happen using different approaches [30][31][32][33][34], including the holographic Sakai-Sugimoto model at nonzero chemical potential [11]. We mention this because the geometric reading in [11] is very similar to ours, since applying a magnetic field makes the D8 and D8 branes to bend closer to the horizon causing an early restoration of the chiral symmetry.…”

“…However, it is also well known from lattice calculations [9] and linear sigma models [10] that for some mesons, such as the neutral pion, the magnetic field has the opposite effect on both, its mass and dissociation temperature. It then becomes necessary to find a manner in the gauge/gravity correspondence to reproduce this inverse magnetic catalysis (IMC) for meson dissociation (IMC for other physical phenomena has been reported in various holographic models [11][12][13]).…”

Chiral symmetry breaking and restoration in 2+1 dimensions from holography: Magnetic and inverse magnetic catalysis

“…Further, one can note that the soft wall linear spectrum persists in 2+1 dimensions, as has been shown in the Appendix of ref. [31]. There, one uses the dilaton constant k in units of the string tension.…”