Remote-excitation and remote-detection of single quantum dot using propagating surface plasmons on silver nanowire

TL;DR

This paper demonstrates remote excitation and detection of single quantum dots using propagating surface plasmons on silver nanowires, enabling spatially selective optical control and sensing applications.

Contribution

It introduces a method for remote quantum dot excitation and detection via surface plasmons on silver nanowires, allowing multi-QD control and enhanced spatial selectivity.

Findings

Remote excitation of QDs at microns distance from laser spot.

Simultaneous multi-QD remote detection achieved.

Selective excitation of closely spaced QDs enabled by surface plasmon confinement.

Abstract

Using propagating surface plasmons (SPs) on silver nanowire (NW), we demonstrate that focused laser light at the end of silver nanowire can excite single quantum dot (QD) microns away from the excitation spot. The QD-NW interaction allows the excited QD convert part of its energy into propagating SPs which then can be detected at the remote sites. Simultaneous multi-QDs remote-excitation and detection are also realized. Furthermore, the tight confinement of propagating SPs around the NW surface enables selective excitation of QDs very close in space, which cannot be realized under conventional excitation condition. This remote excitation and detection approach may find applications in optical imaging and sensing of chemical and biological systems.