Related Experiment Video
Updated: May 28, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Dense lying self-organized GaAsSb quantum dots on GaAs for efficient lasers.
Thomas H Loeber1, Dirk Hoffmann, Henning Fouckhardt
1Optoelectronics and Microoptics Research Group, Physics Department, Kaiserslautern University of Technology, P.O. Box 3049, D-67653 Kaiserslautern, Germany.
Beilstein Journal of Nanotechnology
|October 7, 2011
Summary
This study details the growth of Gallium Arsenide Antimonide (GaAsSb) quantum dots (QDs) using Stranski-Krastanov epitaxy. The research achieved dense QD formation and demonstrated an efficient quantum dot laser emitting near 0.900 µm.
Area of Science:
- Materials Science
- Semiconductor Physics
- Nanotechnology
Background:
- Quantum dots (QDs) are crucial for advanced optoelectronic devices.
- Gallium Arsenide Antimonide (GaAsSb) offers tunable bandgaps for specific emission wavelengths.
- Epitaxial growth methods are key to controlling QD properties.
Purpose of the Study:
- To investigate the influence of V/III flux ratio and growth temperature on GaAsSb quantum dot characteristics.
- To optimize growth parameters for dense and uniform QD formation.
- To fabricate and demonstrate an efficient electrically pumped GaAsSb quantum dot laser.
Main Methods:
- Stranski-Krastanov (SK) epitaxial growth mode was employed for GaAsSb QD synthesis on GaAs substrates.
- Growth parameters, including Sb/Ga (V/III) flux ratio (0.45/1 to 1.50/1) and temperature (445–580 °C), were systematically varied.
- Photoluminescence (PL) spectroscopy was used to analyze QD emission properties.
- Fabrication of a stacked QD layer structure for laser demonstration.
Main Results:
- Dense GaAsSb quantum dot layers with densities up to 6.5 × 10^10 cm^-2 were achieved.
- Optimized growth conditions yielded QDs with a diameter of 20 nm and height of 4 nm.
- Photoluminescence spectra showed tunable emission wavelengths between 0.876 and 1.035 µm.
- An efficient electrically pumped quantum dot laser was realized, emitting at λ ≈ 0.900 µm at 84 K.
Conclusions:
- The study successfully optimized GaAsSb quantum dot growth using specific V/III ratios and temperatures.
- The developed QD material enables the fabrication of efficient lasers in the 0.9 µm range.
- This work contributes to the development of novel semiconductor laser technologies.
