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Bias-polarity dependent ultraviolet/visible switchable light-emitting devices
Pei-Nan Ni1, Chong-Xin Shan, Bing-Hui Li
1State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences , Changchun 130033, China.
ACS Applied Materials & Interfaces
|May 9, 2014
Summary
Researchers developed switchable ultraviolet/visible light-emitting devices using semiconductors. By altering the electric field
Area of Science:
- Materials Science
- Solid-State Physics
- Optoelectronics
Background:
- Semiconductors with varying band-gap energies are crucial for tunable light emission.
- Electric field control over electron-hole recombination is key for device functionality.
Purpose of the Study:
- To realize bias-polarity dependent ultraviolet/visible switchable light-emitting devices.
- To explore the potential for multicolor-switchable light emission.
Main Methods:
- Fabrication of Au/MgO/Mg0.49Zn0.51O/MgxZn1-xO/n-ZnO heterostructures.
- Utilizing semiconductors with different band-gap energies as active layers.
- Controlling the electron-hole recombination region via electric field manipulation.
Main Results:
- Demonstrated bias-polarity dependent switching between ultraviolet and visible (orange) light emission.
- Successfully tuned emission bands by changing the applied bias polarity.
- Achieved switchable light emission in novel semiconductor structures.
Conclusions:
- The developed device structure offers a feasible approach for multicolor-switchable light-emitting applications.
- Bias-polarity control provides a viable method for tuning light emission characteristics.
- This work contributes to the development of advanced optoelectronic devices.
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