Seminars

2D materials with reduced dimensionality exhibit unprecedented tunability in both their electronic and optical properties due to the high susceptibility to the doping and the change of many-electron effects. Here we demonstrate a tunable quasiparticle band gap and excitonic effects in back-gated 2D material devices. Using low-temperature scanning tunnelling microscopy (LT-STM), we probed gate-tunable correlation and excitonic effects of recently-emerged 2D materials including few-layer black phosphorus (BP) and monolayer TMDs. The demonstration of field-tunable band gap and excitonic...