223 / 2024-07-26 14:07:48

Tip-induced nano-spectroscopic electric pulse modulator for deterministic local electron density control

Carrier density,Nano-spectroscopy,Quantum yield,Doping,Transition metal dichalcogenide

Controlling electron density in two-dimensional semiconductors is crucial for both a comprehensive understanding of fundamental material properties and their technological applications. However, conventional electrostatic doping methods exhibit limitations, particularly in addressing the electric-field-induced drift and subsequent diffusion of electrons, which restrict the spatio-temporally deterministic doping control at the nanoscale region. Here, we present a tip-induced nano-spectroscopic electric pulse modulator to dynamically control the nanoscale electron density, thereby facilitating the precise measurement of nano-optoelectronic behaviors within a MoS2 monolayer. The tip-induced electric pulse enables the nanoscale modulation of the electron distribution as a function of the electric pulse width. We simultaneously investigate the spatially altering photoluminescence quantum yield at the nanoscale region. We model the extent of the electron depletion region, confirming a minimum doping region with a radius of ∼290 nm for a pulse width of 30 ns. Our approach paves the way for the deterministic engineering of the local electron density and in-situ nano-optical characterization in two-dimensional materials, enabling an in-depth understanding of doping-dependent nano-optoelectronic phenomena.