Enhanced transient THz response in TMDC heterostructures

The THz conductivity of MoS
2
, MoSe
2
monolayers and their heterostructure is compared and reported here. We also measured the hot carrier relaxation upon optical excitation in these samples below and above the bandgap of the monolayers. While in the heterostructure the recovery kinetics of the carriers resembles that of monolayers, the conductivity change is enhanced by one order of magnitude. A simple model accounts for this phenomenon.