Fabrication, Characterization, and Integration of In(Ga)As Semiconductor Quantum Dots for Telecommunication Wavelengths

The concepts of quantum computing and cryptography are based on superposition states of a two-level system, the qubits. One possible realization of a qubit is the polarization state of a single photon. In this regard, InGaAs/GaAs semiconductor quantum dots have been studied as sources for single photons and entangled photon pairs and, in the case of communication via optical fiber networks, emission wavelengths in the telecom bands at 1.31 µm and 1.55 µm.

This work presents research on the growth of InGaAs quantum dots on GaAs substrates by metal-organic vapor-phase epitaxy. The focus lies on the study of growth parameters for low area densities of quantum dots with emission wavelengths at 1.31 µm and the optical characterization of single quantum dots as sources for non-classical light. Furthermore, approaches towards the site-controlled growth of these quantum dots as well as the integration into optical devices and functionalized structures are introduced.