Plug-and-play quantum devices with efficient fiber-quantum dot interface

TL;DR

This paper presents a highly efficient, stable, plug-and-play fiber-coupled quantum dot single-photon source that simplifies integration into fiber networks for quantum communication.

Contribution

It introduces a novel fiber-interfacing photonic device with optimized structures and a pick-and-place technique for stable, alignment-free quantum light transmission.

Findings

Achieved direct coupling of quantum dot photons into standard fiber with high efficiency.

Developed a plug-and-play device that requires no optical alignment.

Demonstrated long-term stable quantum light transmission over fiber.

Abstract

Incorporating solid-state quantum emitters into optical fiber networks enables the long-distance transmission of quantum information and the remote connection of distributed quantum nodes. However, interfacing quantum emitters with fiber optics encounters several challenges, including low coupling efficiency and stability. Here, we demonstrate a highly efficient fiber-interfacing photonic device that directly launches single photons from quantum dots into a standard FC/PC-connectorized single-mode fiber (SMF28). Optimally designed photonic structures based on hole gratings produce an ultra-narrow directional beam that matches the small numerical aperture of a single-mode fiber. A pick-and-place technique selectively integrates a single miniaturized device into the core of the fiber. Our approach realizes a plug-and-play single-photon device that does not require any optical alignment and thus guarantees long-term stability. The results thus represent a major step toward practical and reliable quantum lights across a fiber network.