AdS$_2$ near-horizons, defects and string dualities

Abstract: We construct a new family of $\text{AdS}_2\times S^3\times S^2$ solutions to Type IIB supergravity arising as near-horizon geometries of D1-F1-D3-D5-NS5-D7 brane intersections preserving 4 supersymmetries. We show that a subclass of these solutions asymptotes locally to the $\text{AdS}_6\times S^2\times \Sigma_2$ solution to Type IIB supergravity holographically dual to the five dimensional Sp(N) fixed point theory. This suggests that these solutions can be interpreted as D1-F1-D3 line defects within this CFT. Switching off the D7-branes, we act with $\text{SL}(2, \mathbb{R})$ to construct a second family of solutions that can be related to an $\text{AdS}_3\times S^3\times S^3$ class of M-theory backgrounds describing surface defects within the six dimensional (1,0) SCFT dual to $\text{AdS}_7/\mathbb{Z}_k\times S^4$. Finally, using non-Abelian T-duality we construct new classes of $\text{AdS}_2\times S^2\times S^2$ solutions to Type IIA supergravity with 4 supercharges and elaborate on their M-theory origin.