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
Arakawa River (Fukushima) The name Arakawa comes from the river long being known as an , meaning a river that floods often. Due these floodings, the Arakawa River has changed its course multiple times. The Ōmori River, now a tributary of the Arakawa River, currently flows in the former main riverbed of the Arakawa River. The Arakawa River's steep descent in the Tsuchiyu Onsen area formerly caused multiple earth and rock slides. To prevent further damage, in 1900 Fukushima Prefecture began flood control construction on the river, and in 1936 the country took over and began construction of the . The construction proved