2D Semiconductor Optoelectronics: Advances, Challenges and Opportunities

In this talk, I will present recent advancements on understanding and controlling the radiative and non-radiative recombination rates in various 2D semiconductor systems. I will discuss the mechanisms by which non-radiative recombination can be fully suppressed in TMDC monolayers, resulting in near-unity photoluminescence quantum yield at room temperature despite the presence of large defect densities.  I will discuss an AC carrier injection mechanism to enable bright light emitting devices using monolayers, overcoming the problem of Schottky contacts. Finally, I will discuss potential applications for black phosphorous (BP) thin films for midwave-IR photo detection and emission. Specifically, the BP based devices are shown to exhibit higher detectivity and luminescence efficiencies over state-of-the-art III-V and II-VI devices in mid-IR, owing to the lower Auger recombination rates and surface recombination velocity.