In this talk, I will discuss polaron excitations in ultracold atomic gases of fermions. Defined as
collective excitations induced by an impurity, polaron is a typical quasiparticle that has stimulated
much interest in the study of solid-state and cold-atom systems with highly polarized components.
In cold atomic systems with highly controllable environment, new types of polarons may be prepared. I
will focus on two scenarios, in which exotic polaron excitations may emerge under specifically designed
backgrounds and interactions. I will also discuss possible experimental detection of these polarons.