White-Light GaN-μLEDs Employing Green/Red Perovskite Quantum Dots as Color Converters for Visible Light Communication
Xiaoyan Liu1, Langyi Tao1, Shiliang Mei2
1College of Integrated Circuit Science and Engineering, and National and Local Joint Engineering Laboratory for RF Integration and Micro-Packaging Technologies, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
Nanomaterials (Basel, Switzerland)
|February 26, 2022
Summary
This study introduces white-light micro-LEDs using perovskite quantum dots for faster visible light communication and solid-state lighting. These GaN-based micro-LEDs overcome limitations of traditional phosphors, enabling simultaneous high-speed wireless optical communication and illumination.
Area of Science:
- Optoelectronics
- Materials Science
- Photonics
Background:
- Gallium Nitride (GaN)-based micro-light-emitting diodes (μLEDs) are crucial for micro-displays, illumination, and visible light communication (VLC).
- Conventional white-light LEDs use yttrium aluminum garnet (YAG) phosphors, limiting communication bandwidth due to their slow response times.
Purpose of the Study:
- To propose and demonstrate white-light GaN-based μLEDs utilizing perovskite quantum dots (PQDs) as color converters for enhanced visible light communication (WL-VLC) and solid-state lighting (SSL).
- To investigate the communication and illumination performance of these novel WL-VLC systems.
- To optimize WL-VLC performance by studying the properties of green and red PQDs.
Main Methods:
- Fabrication of white-light GaN-μLEDs by combining blue InGaN-μLEDs with green/red PQDs as replacements for YAG phosphors.
- Systematic investigation of communication and illumination performances of the developed WL-VLC system.
- Characterization of VLC properties for monochromatic green and red light emitted by PQDs.
Main Results:
- Achieved modulation bandwidths of 162 MHz for blue InGaN-μLEDs, 64 MHz for green PQDs, and 90 MHz for red PQDs.
- Demonstrated a white-light bandwidth of 57.5 MHz and CIE coordinates of (0.3327, 0.3114) for the WL-VLC system.
- Successfully generated white light using PQDs with narrow emission spectra and short fluorescence lifetimes.
Conclusions:
- White-light GaN-based μLEDs with PQDs show significant potential for simultaneous VLC and SSL applications.
- These findings pave the way for high-performance micro-displays utilizing PQDs as color-conversion materials.
- The use of PQDs offers a promising direction for overcoming bandwidth limitations in current white-light LED technologies.
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