Concluded Projects

In our project UNIQORN on Affordable Quantum Communication for Everyone we exploit the high effective optical nonlinearity of our AlGaAs waveguides and the low-loss polymer structures of our collaborators at the HHI in Berlin in a hybrid approach. Our Bragg-reflection waveguides act as a source of photon pairs at the telecom wavelength range, which are subsequently time-bin entangled in on-chip polymer michelson interferometers.

In our project IGUANA on Integrated Quantum Rangefinding we utilize the photon pairs produced in our Bragg-reflection waveguides for a quantum protocol for remote sensing. Inspired by quantum illumination it hinges on the thermal photon-pair probability distribution generated by parametric down-conversion. Different from quantum illumination, the protocol does not offer an improved signal-to-noise ratio, but perfect covertness guaranteed by the laws of quantum mechanics.

In our project on Entangled Photon Pairs from Semiconductor Waveguides we were able to exploit the large optical nonlinearities that the AlGaAs material platform offers via Bragg-reflection waveguides (BRWs). We have shown the capabilities of these devices in generating entangled photon pairs and achieved difference frequency generation with an on-chip quantum dot laser. The success of this project has allowed us to acquire funding for exciting follow-up research in the form of the UNIQORN, Beyond-C, IGUANA and another D-A-CH project.

In our project on microcavity polaritons we trap light in special semiconductor nanostructures to make it strongly interacting with electronic states in the GaAs-AlGaAs hetero structure. We investigate the opportunities to utilize these half-light, half-matter quasi-particles for generation of non-classical polariton states and quantum states of light