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Epitaxial Nanostructures Group

Epitaxial nanostructures group studies the fabrication technologies of semiconductor nanostructures like quantum dots (QDs) by means of molecular beam epitaxy and metalorganic chemical vapor deposition. The group also addresses the growth mechanism of nanostructures by observing the atomic arrangements of growth surface with scanning tunneling microscope (STM) and reflection high-energy electron diffraction (RHEED). The final goal is to make useful and fascinating quantum-effect devices which are applicable to the fields such as energy & environment, security, medical and biological applications as well as information and communication technology.

Specialized Research Field

Fabrication of Semiconductor Epitaxial Nanostructures

Epitaxial nanostructures group is devoted to the development of GaAs QDs growth technique by using the droplet epitaxy, which was invented at NRIM, the former Institute of NIMS. Besides improving the optical quality of QDs, our group has successfully made a variety of nanostructures including QD pairs and rings, and has clarified their optical and electronic properties. Recently, it was revealed that both the shape and the energy states of QDs can be tuned if they are grown on the higher index substrates. STM and RHEED studies help us to understand the formation mechanism of nanostructures and to control the growth at higher index surfaces. Our research group is also studying other epitaxial nanostructures such as droplet QDs of GaSb/GaAs system having type-II energy band and a novel approach using the exciton bound to intentionally-doped individual isoelectronic impurity atom or pair.

Group Leader

"Yoshiki SAKUMA" Image

Yoshiki SAKUMA

Inquiry about this page

1-1 Namiki, Tsukuba, Ibaraki, 305-0044 JAPAN
TEL. +81-29-860-4299
E-Mail: SAKUMA.Yoshiki=nims.go.jp(Please change "=" to "@")
National Institute for Materials Science (NIMS)
1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, JAPAN