Related Experiment Video
Updated: Jun 22, 2025
10:36
Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
Published on: April 12, 2018
11.5K
Electrically tunable non-radiative lifetime in WS2/WSe2 heterostructures
Anran Wang1, Xingguang Wu2, Siwen Zhao2
1School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, China. fwang@nju.edu.cn.
Nanoscale
|July 5, 2024
Summary
Electrical control of exciton dynamics in transition metal dichalcogenide (TMD) heterostructures is achieved. Non-radiative relaxation lifetimes of photocarriers are modulated by back-gate voltage, enabling tailored light-matter interactions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Optoelectronics
Background:
- Transition metal dichalcogenide (TMD) heterostructures exhibit unique physical properties for optoelectronics and valleytronics.
- Controlling exciton relaxation dynamics is vital for optimizing TMD-based devices.
Purpose of the Study:
- Investigate the influence of back-gate voltage on exciton dynamics in WS2/WSe2 heterostructures.
- Explore the role of twist angles and doping in modulating carrier relaxation pathways.
Main Methods:
- Employed time-resolved photoluminescence (TRPL) and transient absorption spectroscopy (TAS).
- Conducted experiments at cryogenic temperatures on WS2/WSe2 heterostructures with varying twist angles.
- Utilized back-gate modulation to control carrier populations.
Main Results:
- Demonstrated electrical control over non-radiative relaxation lifetimes in WS2/WSe2 heterostructures.
- Observed that lifetime tuning is absent in standalone TMD monolayers.
- Attributed tunable lifetimes to doping-controlled competition between interlayer and intralayer recombination.
Conclusions:
- Back-gate modulation offers a pathway to actively control exciton dynamics in TMD heterostructures.
- Understanding recombination pathways is key to designing advanced optoelectronic and valleytronic devices.
- Simultaneous TRPL and TAS measurements provide comprehensive insights into photo-carrier behavior.
