A recipe for exotic 2-links in closed 4-manifolds whose components are topological unknots

We describe a construction procedure of infinite sets of 2-links in closed simply connected 4-manifolds that are topologically isotopic, smoothly inequivalent and componentwise topologically unknotted. These 2-links are the first such examples in the literature. The examples provided have surface and free groups as their 2-link groups, and display subtle exotic phenomena that are related to their linking. In particular, our examples are not parallel copies of exotic embeddings of 2-spheres that were previously known to exist nor their combinations with smoothly unknotted 2-spheres.