Yasuhiko Arakawa Yasuhiko Arakawa Yasuhiko Arakawa (Japanese , "Arakawa Yasuhiko"; born 6 November 1952) is a Japanese physicist. His research focuses on semiconductor physics, including growth of nanostructures and their optoelectronic applications. Among his main achievements are the proposal of the concept of quantum dots and their application to quantum dot lasers, the observation of exciton-polariton Rabi-splitting in a semiconductor microcavity, or, recently, the first 3D photonic crystal nanocavity lasers with quantum dot gain. Yasuhiko Arakawa received a B.S. degree in 1975 and a Ph.D. degree in 1980, respectively, from the University of Tokyo, both in Electronics Engineering. In 1981 he became
Sumida M.2593 had a crew of six men, and was armed with either one 6.5 mm machine gun or one 7.7 mm machine gun. One version, the Type 91 Armored Railroad Car So-Mo was produced without a main fixed machine gun for armament. A second variant produced by Ishikawajima was known as the Sumida Model P Armored Car. It was used by the Special Naval Landing Forces (SNLF) of the Imperial Japanese Navy (IJN). Sumida M.2593 The Sumida M.2593 (Type 91) was an armoured car produced in Japan in the 1930s. It could operate on both the roadway and railway lines. Designed