AdS2 near-horizons, defects, and string dualities

We construct a new family of AdS2×S3×S2 solutions to type IIB supergravity arising as near-horizon geometries of D1-F1-D3-D5-NS5-D7 brane intersections preserving four supersymmetries. We show that a subclass of these solutions asymptotes locally to the AdS6×S2×ς2 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 SL(2,R) to construct a second family of solutions that can be related to an AdS3×S3×S3 class of M-theory backgrounds describing surface defects within the six-dimensional (1,0) SCFT dual to AdS7/Zk×S4. Finally, using non-Abelian T-duality we construct new classes of AdS2×S2×S2 solutions to type IIA supergravity with four supercharges and elaborate on their M-theory origin.