Intra-excitonic spectroscopy of a Mott insulator

Excitons are traditionally studied in weakly interacting semiconductors where Coulombic binding is dominant, resulting in highly predictable, hydrogen-like states. However, far less is understood about excitons in strongly correlated electron systems, which exhibit complex interactions between charge, spin, orbital, and lattice degrees of freedom at energy scales relevant for excitonic binding. In this talk, I will discuss recent ultrafast time-resolved time-domain THz spectroscopy measurements directed at searching for signatures of intra-excitonic transitions in Mott antiferromagnets. Spectroscopic evidence of transient exciton formation will be compared against numerical calculations.