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Updated: Feb 5, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
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InAs/GaAs Quantum Dot Dual-Mode Distributed Feedback Laser Towards Large Tuning Range Continuous-Wave Terahertz
Qi-Zhu Li1,2, Yuan-Qing Huang1,3, Ji-Qiang Ning4
1Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, People's Republic of China.
Nanoscale Research Letters
|September 6, 2018
Summary
This study presents a novel quantum dot laser with wide tunable dual-wavelength operation. This advanced distributed feedback laser offers a broad tuning range for continuous-wave terahertz radiation generation.
Area of Science:
- Semiconductor lasers
- Quantum dot devices
- Photonics and optoelectronics
Background:
- Distributed feedback (DFB) lasers are crucial for wavelength-selective light emission.
- Quantum dot (QD) structures offer unique optoelectronic properties for laser applications.
- Achieving wide tunable dual-wavelength operation in a single device remains a challenge.
Purpose of the Study:
- To fabricate and characterize a laterally coupled distributed feedback (LC-DFB) laser using modulation p-doped InAs/GaAs quantum dot structures.
- To investigate the device's performance, including side-mode suppression ratio (SMSR) and thermal stability.
- To demonstrate wide tunable dual-wavelength lasing operation and explore its potential for terahertz (THz) radiation generation.
Main Methods:
- Fabrication of LC-DFB lasers utilizing modulation p-doped multiple InAs/GaAs QD structures.
- Characterization of laser performance under continuous-wave (CW) operation, including SMSR and thermal stability (dλ/dT).
- Tuning of dual-wavelength operation by adjusting grating periods or cavity length.
Main Results:
- The fabricated LC-DFB laser achieved a high SMSR of >47 dB and excellent thermal stability (dλ/dT = 0.092 nm/K).
- Wide tunable dual-wavelength lasing was successfully demonstrated with wavelength spacing tunable from 0.5 to 73.4 nm (0.10 to 14 THz).
- This represents the largest tuning range achieved with a single device.
Conclusions:
- The modulation p-doping and rapid thermal annealing (RTA) process, combined with shallow-etched gratings, significantly enhance material gain and reduce waveguide losses.
- The developed LC-DFB laser provides a flexible platform for generating tunable dual-wavelength emission.
- This technology offers a promising new avenue for the generation of continuous-wave (CW) terahertz (THz) radiation.
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