Atomic Scale Characterization of Single Photon Emitters with STM

Within the vast set of defects observed in 2D materials, the optically active substitutional defects of transition metal dichalcogenides are particularly interesting due to quantum memory and sensing applications they promise as single photon emitters. However, the optical properties of these materials and the modifications caused by their heterogeneities are usually studied in mesoscopic scales. Which gives a response averaged from an ensemble of defects. The one-to-one correlations between the atomic structure of the defects and their specific role in the optical response remains unclear. Furthermore, optoelectronic properties of structurally identical defects may differ due to local strain and charge transfer landscape around them. Scanning Tunneling Microscopy (STM) provides a unique tool to study these quantum emitters as it can investigate the atomic structure of defects and their influence on the electronic properties of the host lattice.

Using STM's atomic-scale imaging and spectroscopy capabilities, we study the structural and electronic properties of various 2D materials that host single photon emitters. Here we present a summary of these studies and our ongoing efforts to add co-registered, atomic scale optical characterization capabilities to these measurements.