This InstituteQ Colloquium features Dr. Bruno Schuler, a research group leader at the Swiss Federal Laboratories for Materials Science and Technology. The title of his talk is "Ultrafast and Ultrasmall: Probing 2D Semiconductors with Lightwave-Driven THz-STM."
Event details
When: 14.00-15.00, 31.5.2024
Where: Ekonominaukio 1, Hall V002, Otaniemi
Register: Webropol link to register
From Bruno Schuler: What will your talk discuss?
Two-dimensional (2D) semiconductors provide an exciting platform to engineer atomic quantum systems in a robust, yet tunable solid-state system. In this colloquium, I will present our efforts to unravel the interesting physics behind single dopant atoms in transition metal dichalcogenide (TMD) monolayers by means of high-resolution scanning probe microscopy. By targeted chemical doping of semiconducting TMDs, we identify the interplay between chemical impurity states, multi-valley hydrogenic bound states, spin-orbit coupling, and electron-phonon interaction at reduced dimensions.
I will provide an overview on our ongoing developments of an ultrafast lightwave-driven scanning tunneling microscope using single-cycle THz pulses to measure the sub-picosecond time dynamics at atomic spatial resolution. Mapping of the THz rectified charge as a function of dc bias and THz field amplitude ("QEV map") facilitates a precise calibration of the near-field transient bias and navigating the energy landscape for state-selective tunneling into specific defect states or TMD bands.