Probing into Intraband Transitions Enabled Charge Carrier Dynamics of THz Response Generated in Graphene/MoS Heterostructures.

The engineering of terahertz phonons is challenging due to difficulties in achieving sub-nanometer material precision and in facilitating efficient phonon coupling at terahertz frequencies region. The effective generation, detection, and manipulation of terahertz phonons via the integration of atomically thin layers in van der Waals heterostructures can enable new designs for next-generation optoelectronic quantum devices, offering new avenues for thermal engineering in the terahertz regime. Here, optical pump terahertz probe and terahertz time-domain experiments are used to reveal the behavior of charge carrier transfer in real time at heterostructure interfaces of single-layer graphene and monolayer MoS upon photoexcitation and plausible mechanism has been put forward.