D-instantons in Klebanov-Witten model

TL;DR

This paper explores D-instanton solutions in type IIB supergravity on AdS5×T^{1,1}, linking them to dual super Yang-Mills instantons with specific charges, and analyzes their boundary behavior and physical implications.

Contribution

It introduces explicit D-instanton solutions including wrapped D1-branes in the Klebanov-Witten model, connecting supergravity solutions to dual gauge theory instantons with detailed boundary analysis.

Findings

Explicit D-instanton solutions with supersymmetry preservation.

Identification of solutions with (anti)self-dual Yang-Mills instantons.

Analysis of boundary operators and vacuum expectation values.

Abstract

We study D-instanton solutions in type IIB supergravity on $AdS_5\times T^{1,1}$, which has a dual ${\cal N}=1$ $SU(N)\times SU(N)$ super Yang-Mills theory. Apart from ordinary D(-1)-brane instantons, we discuss wrapped D1-branes over minimal 2-cycles and derive explicit solutions preserving half the supersymmetries. These solutions are identified with Yang-Mills instantons which are (anti)self-dual in both gauge group factors with instanton charge $(k,k')$. By examining the boundary behaviour of the solutions we discuss the coupling to the corresponding dual boundary operators, and identify their vacuum expectation values. We also discuss the boundary terms and compute the action for these solutions.