Highly Pure and Bright Emission of Telecom C-Band Quantum Dots in Circular Bragg Grating Cavities

Many prospective quantum technology applications, such as for instance quantum communication, rely on the availability of carrier of quantum information. For this purpose, single photons can be used as “flying qubits” encrypting the information for instance in the polarization state [1]. Among other potential candidates for sources of single-photons are semiconductor quantum dots (QDs) which can provide high photon rates and scalable infrastructure using photonic integrated circuits. Especially QD emission with wavelength in the telecom C-band is highly sought-after for applications due to the low transmission loss in fibers and free space as well as the compatibility to the well-developed silicon photonics platform.