Extended operators in QFT

[blefloch]

• Wilson loop, 't Hooft loop, dyonic loop
• vortex loop in 3d
• surface operators (monodromy, or couple to lower dimensional theory)
• duality walls
• Dirichlet boundary condition
• Neuman(n?) boundary condition
• http://arxiv.org/abs/hep-th/0306001 about D-branes in topologically twisted N=2 minimal models
• FZZT and ZZ branes in Liouville CFT

[blefloch]

Walls:

• Erdmenger Guralnik Kirsch 4d N=2 & 3d N=2
• Gaiotto Witten 4d N=4 & 3d N=4 boundaries, Janus Wall and S-duality
• Cherkis O'Hara Saemann 4d N=2 & 3d N=2

[blefloch]

Gadde Gukov Putrov generalities about codimension 2 duality defects which are end-points of duality walls (has a bunch of interesting refs).