Mesons and Higgs branch in defect theories

TL;DR

This paper investigates the Higgs branch of a defect theory created by intersecting D3- and D5-branes, analyzing supersymmetric configurations, brane polarization, and the spectrum of mesonic bound states, revealing a continuous and gapless spectrum.

Contribution

It introduces a supersymmetric D3-D5 brane configuration with worldvolume flux, connecting brane polarization to the Higgs branch in the dual defect field theory.

Findings

D5-brane can be viewed as polarized D3-branes.

The Higgs branch corresponds to a supersymmetric brane embedding.

Mesonic spectrum in the Higgs branch is continuous and gapless.

Abstract

We consider the defect theory obtained by intersecting D3- and D5-branes along two common spatial directions. We work in the approximation in which the D5-brane is a probe in the AdS_5xS^5 background. By adding worldvolume flux to the D5-brane and choosing an appropriate embedding of the probe in AdS_5xS^5, one gets a supersymmetric configuration in which some of the D3-branes recombine with the D5-brane. We check this fact by showing that the D5-brane can be regarded as a system of polarized D3-branes. On the field theory side this corresponds to the Higgs branch of the defect theory, where some of the fundamental hypermultiplet fields living on the intersection acquire a vacuum expectation value. We study the spectrum of mesonic bound states of the defect theory in this Higgs branch and show that it is continuous and gapless.