Efficient quantum dot single photon extraction into an optical fiber using a nanophotonic directional coupler

TL;DR

This paper presents a broadband, efficient method for collecting single-photon emission from quantum dots directly into optical fibers using a nanophotonic directional coupler, enhancing quantum photonics applications.

Contribution

The authors introduce a novel broadband nanophotonic directional coupler that significantly improves photon collection efficiency from quantum dots into optical fibers.

Findings

Achieved a maximum collection efficiency of 6.05% into a single-mode fiber.

Demonstrated broadband collection over tens of nanometers.

Estimated a single-photon rate of 3.0 MHz for a quantum dot.

Abstract

We demonstrate a spectrally broadband and effcient technique for collecting photoluminescence from a single InAs quantum dot directly into a standard single mode optical fiber. In this approach, an optical fiber taper waveguide is placed in contact with a suspended GaAs nanophotonic waveguide with embedded quantum dots, forming an effcient and broadband directional coupler with standard optical fiber input and output. Effcient photoluminescence collection over a wavelength range of tens of nanometers is demonstrated, and a maximum collection effciency of 6.05 % (corresponding single photon rate of 3.0 MHz) into a single mode optical fiber was estimated for a single quantum dot exciton.