Atomic Scale Plasmonic Devices

The arrival of the Single-Atom Transistor (SAT) in 2004, a quantum device operated at room temperature, allowed for the first controlled switching of an electrical current by the reproducible relocation of one single metal atom [1]. At the same time this component established the feasibility of transistors completely made of metals. Meanwhile, many experiments have followed, demonstrating the control of this three-terminal device on the atomic level and even showing a first simple integrated circuit [2]-[4]. A comparable device for plasmonic switching has not been realized yet. However, the fact that this Single Atom Transistor is made of silver - which is an ideal metal for plasmonics - opens intriguing perspectives for combining electronic and plasmonic switching in one and the same device at the atomic level.In this paper, we will demonstrate that photonic scaling is only limited by the atom. In particular we will present a novel plasmonic switch and photodetector featuring digital response at atomic scale. The principle of operation is based on the light-atom interaction in a memristive filament [5].