Dr.
Takaaki Mano, Senior Researcher, and Dr. Masafumi Jo, Researcher, of the Photonic Materials Unit (Managing Director: Kazuaki Sakoda), National Institute for Materials Science (President: Sukekatsu Ushioda) realized a red light quantum dot laser using an original technique developed by NIMS. Although the quantum dot lasers have attracted great interest as important devices for the future, among these devices, fabrication of a high quality red quantum dot laser had been particularly difficult until now.
In this research, new improvements were added to the quantum dot self-assembly technique called droplet epitaxy, which was developed independently at NIMS before. As a result, the NIMS researchers succeeded in realizing laser oscillation from a quantum dot laser using gallium arsenide (GaAs) quantum dots, which emit light in the red wavelength band.
Realization of red laser oscillation was possible because Dr. Mano and Dr. Jo succeeded in developing a technique which dramatically improves the homogeneity of the quantum dots and greatly increasing the number of quantum dots contributing to laser oscillation by layering of those quantum dots. With these developments, laser oscillation was achieved by injection of an electric current.
As a result of this achievement, high performance quantum dot lasers can also be applied to the red region. This is expected to make a significant contribution to higher performance in information and medical devices, among others.
Details of this technology were published in the online edition of the English physics-related science journal “Nanotechnology”, and in the print version of that journal for August 19 (No. 33).
