Holographic Schwinger effect with Translational Symmetry Breaking

TL;DR

We address vacuum instability via the holographic Schwinger effect in a translational-symmetry-breaking background. Using a Wilson-loop/probe-brane setup, we compute the total potential $V_{\text{tot}}$ for a quark–antiquark pair and extract the critical field $E_c$ across subcritical, critical, and supercritical regimes, including the effects of a magnetic field $B$. The results show that the disorder parameter $\alpha$ suppresses pair production by raising the barrier, while the chemical potential $\mu$ promotes it by lowering the barrier; a magnetic field lowers the barrier in general and can enhance the effect even below $E_c$ (i.e., $\beta<1$). The findings elucidate the competing roles of momentum relaxation, density, and magnetic backgrounds in non-perturbative holographic Schwinger processes, with implications for strongly coupled systems under external fields.

Abstract

The effect of disorder on the Schwinger effect at finite chemical potential has been studied from holography. The gravitational background with translational symmetry breaking, characterized by two parameters: the disorder strength \(α\) and the chemical potential \(μ\). By employing the potential analysis method, we derive the total potential that governs the pair creation process and examine its dependence on \(α\), \(μ\), and the the external electric field to its critical value ratio. We analyze the system both in the absence and in the presence of an external magnetic field. Our results show that increasing the chemical potential \(μ\) lowers the potential barrier, thereby enhancing vacuum instability and facilitating pair production, while the disorder parameter \(α\) acts oppositely, suppressing the Schwinger effect by strengthening the barrier. Furthermore, we find that an external magnetic field plays a role similar to the chemical potential by reducing the barrier height and promoting pair creation, even in the subcritical regime. The combined analysis highlights the competing influences of \(μ\) and \(α\), and the amplifying effect of the magnetic field, on the non-perturbative pair production mechanism in holographic setups with broken translational symmetry.

Figures (9)

• Figure 1: The string profile in the background geometry
• Figure 2: Total potential $V_{tot}$ versus the virtual pair distance $x$, when the magnetic filed is off, $B=0$, the parameter $b=0.4$, $\beta<1$, for a) $\alpha=0$ and b) $\mu=0$
• Figure 3: Total potential $V_{tot}$ versus the virtual pair distance $x$, when the magnetic filed is off, $B=0$, the parameter $b=0.4$, $\beta=1$, for a) $\alpha=0$ and b) $\mu=0$
• Figure 4: Total potential $V_{tot}$ versus the virtual pair distance $x$, when the magnetic filed is off, $B=0$, the parameter $b=0.4$, $\beta=1.2$, for a) $\alpha=0$ and b) $\mu=0$
• Figure 5: Total potential versus for various magnetic field values