Spinful quantum dot coupled to the edge states of a topological insulator

Coupling a local quantum impurity to an interacting one dimensional system leads to striking strongly correlated effects. Here we study a spinful quantum dot coupled to the edge states of a topological insulator modeled by an interacting helical Luttinger liquid. We solve the model exactly using Bethe Ansatz and study the ground state properties of the system including the occupation number of the impurity and its density of states. Explicit expressions for the impurity magnetic susceptibility is derived at zero temperature.