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Updated: Feb 24, 2026

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Charge Carriers Modulate the Bonding of Semiconductor Nanoparticle Dopants As Revealed by Time-Resolved X-ray
Asra Hassan, Xiaoyi Zhang, Xiaohan Liu
1Department of Chemistry, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.
Abstract:
Understanding the electronic structure of doped semiconductors is essential to realize advancements in electronics and in the rational design of nanoscale devices. Reported here are the results of time-resolved X-ray absorption studies on copper-doped cadmium sulfide nanoparticles that provide an explicit description of the electronic dynamics of the dopants. The interaction of a dopant ion and an excess charge carrier is unambiguously observed via monitoring the oxidation state. The experimental data combined with DFT calculations demonstrate that dopant bonding to the host matrix is modulated by its interaction with charge carriers. Furthermore, the transient photoluminescence and the kinetics of dopant oxidation reveal the presence of two types of surface-bound ions that create midgap states.
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