Electrostatic trapping of trions in transition metal dichalcogenides: towards a hybrid, optically active and gate defined quantum dot

Optically active, two-dimensional van der Waals materials, such as the transition metal dichalcogenides (TMDCs), have recently emerged as an exciting platform for novel optoelectronic devices and device physics. Many of the attractive properties of the TMDCs can be attributed to a combination of their large excitonic binding energy and the ability to stack multiple layers together into Van der Waals heterostructures.

The two-dimensional nature and large binding energy allow for large electrostatic fields to be applied, even in plane, without dissociating the excitons that dominate the optical response of the TMDCs. In this work, we present recent results on electrostatic trapping of charges and charged exciton complexes (trions), resulting in the creation of nanowires and nanoscale islands in TMDs that were subsequently probed optically. Lifetime and spectroscopic studies will be shown, demonstrating accurate electrostatic control over the occupation and size of the confining potentials – a first step towards the creation of hybrid, electrically and optically active quantum dots.