Status and key issues for compound semiconductor nanoelectronics

Recent progress of the "nanofabrication" technology has opened up exciting possibilities of constructing novel quantum nanoelectronics directly based on the quantum mechanics where wave-particle motions of individual electrons are controlled by artificial quantum structures such as quantum wells, quantum wires, quantum dots and single and multiple tunneling barriers so as to realize devices with new functions and higher performances. This paper discusses the present status and key issues of research on the compound semiconductor quantum nanoelectronics, introducing recent results obtained by author's group at Research Center for Interface Quantum Electronics (RCIQE) as specific examples. Since electrons manifest predominantly either wave-nature or particle-nature depending on their environments, one can conceptually envisage two kinds of nanoelectronics in the quantum regime, i.e., "quantum wave electronics" and "single electronics". A particular emphasis is paid here on single electronics because of its promising prospects. Main topics include prospects, expected roles and nano-fabrication issues of compound semiconductor single electron devices as well as key issues on compound semiconductor quantum wave devices.