A fiber-integrated nanobeam single photon source emitting at telecom wavelengths

Abstract

Fiber-coupled single photon sources are considered important components of photonics-based quantum information processors. Most fiber-coupled single photon sources require careful alignment between fibers and quantum emitters. In this work, we present an alignment-free fiber-integrated single photon source based on an InAs/InP quantum dot emitting at telecom wavelengths. We designed a nanobeam containing the quantum dots attached to a fiber taper. The adiabatic tapered coupler of the nanobeam enables efficient light coupling to the fiber taper. Using a tungsten probe in a focused ion beam system, we transferred the nanobeam to the fiber taper. The observed fiber-coupled single photon emission occurs with a brightness of 1.4% and a purity of 83%. This device provides a building block for fiber-optic quantum circuits that have various applications, such as quantum communication and distributed quantum computing.