Plasmon-enhanced polarized single photon source directly coupled to an optical fiber

TL;DR

This paper presents a room-temperature, fiber-coupled polarized single photon source enhanced by plasmonic nanorods, achieving high emission enhancement and polarization purity, suitable for quantum networks.

Contribution

It introduces a novel plasmon-enhanced, fiber-coupled single photon source using colloidal quantum dots and gold nanorods on an optical fiber surface, enabling efficient quantum communication.

Findings

Photon emission enhancement of 62 times

Degree of polarization of 86%

Fourfold brightness increase in fiber mode

Abstract

A bright source of fiber-coupled, polarized single photons is an essential component of any realistic quantum network based on today's existing fiber infrastructure. Here, we develop a Purcell enhanced, polarized source of single photons at room temperature by coupling single colloidal quantum dots to the localized surface plasmon-polariton modes of single gold nanorods, combined on the surface of an optical nanofiber. A maximum enhancement of photon emission of 62 times was measured corresponding to a degree of polarization of 86 $\%$, and a brightness enhancement of four times in the fiber mode. Evanescent coupling of photons to the nanofiber guided modes ensures automatic coupling to a single mode fiber. Our technique opens the way to realizing bright sources of polarized single photons connected to fiber networks using a simple composite technique.