Supersymmetric RG flows and Janus from type II orbifold compactification

We study holographic RG flow solutions within four-dimensional N = 4 gauged supergravity obtained from type IIA and IIB string theories compactified on T⁶/Z₂ x Z₂ orbifold with gauge, geometric and non-geometric fluxes. In type IIB non-geometric compactifications, the resulting gauged supergravity has ISO(3) x ISO(3) gauge group and admits an N = 4 AdS₄ vacuum dual to an N = 4 superconformal field theory (SCFT) in three dimensions. We study various supersymmetric RG flows from this N = 4 SCFT to N = 4 and N = 1 non-conformal field theories in the IR. The flows preserving N = 4 supersymmetry are driven by relevant operators of dimensions Δ = 1, 2 or alternatively by one of these relevant operators, dual to the dilaton, and irrelevant operators of dimensions Δ = 4 while the N = 1 flows in addition involve marginal deformations. Most of the flows can be obtained analytically. We also give examples of supersymmetric Janus solutions preserving N = 4 and N = 1 supersymmetries. These solutions should describe two-dimensional conformal defects within the dual N = 4 SCFT. Geometric compactifications of type IIA theory give rise to N = 4 gauged supergravity with ISO(3) x U(1)⁶ gauge group. In this case, the resulting gauged supergravity admits an N = 1 AdS₄ vacuum. We also numerically study possible N = 1 RG flows to non-conformal field theories in this case. (orig.)