Single Atom Plasmonic Switch

TL;DR

This paper introduces a room-temperature, CMOS-compatible single atom plasmonic switch that enables fast, reversible optical switching at the atomic scale with low power consumption, advancing photonic device miniaturization.

Contribution

It demonstrates the first electrically controlled single atom plasmonic switch capable of reversible digital optical switching at room temperature.

Findings

Achieved 10 dB extinction ratio in switching.

Operates at room temperature with femtojoule power per switch.

Supports two distinct plasmonic resonance states depending on atom location.

Abstract

The atom sets an ultimate scaling limit to Moores law in the electronics industry. And while electronics research already explores atomic scales devices, photonics research still deals with devices at the micrometer scale. Here we demonstrate that photonic scaling-similar to electronics-is only limited by the atom. More precisely, we introduce an electrically controlled single atom plasmonic switch. The switch allows for fast and reproducible switching by means of the relocation of an individual or at most -- a few atoms in a plasmonic cavity. Depending on the location of the atom either of two distinct plasmonic cavity resonance states are supported. Experimental results show reversible digital optical switching with an extinction ration of 10 dB and operation at room temperature with femtojoule (fJ) power consumption for a single switch operation. This demonstration of a CMOS compatible, integrated quantum device allowing to control photons at the single-atom level opens intriguing perspectives for a fully integrated and highly scalable chip platform -- a platform where optics, electronics and memory may be controlled at the single-atom level.