I am a Ph.D. student at the Center of Hybrid Quantum Networks (Hy-Q) of the Niels Bohr Institute, in the University of Copenhagen. In the Quantum Photonics group of Hy-Q we aim to develop a solid-state based platform that generates ‘flying qubits’, i.e. photons, to serve as information carriers, for applications towards the quantum internet. More specifically, we use III-V semiconductor quantum dots as our photon emitters, which we embed in specially designed photonic nanostructures, in order to tailor their interaction with light and collect the emitted photons efficiently. With this light-emitter interface the team has demonstrated a deterministic single photon source, which is a key enabler of quantum communication and quantum simulation protocols.
In the project that I work on, we investigate the photon-mediated interaction between pairs of quantum dots, that are sharing the waveguide of a photonic crystal. Even though such a dipole-dipole interaction would decay fast in free-space, in our case the coupling between the quantum dots is extended to multiple wavelengths, benefiting from the photonic environment. This allows us to observe collective effects between our distant coupled emitters, like super- and subradiant emission, as well as the coherent evolution of their rising dynamics throughout time.
By introducing spin inside the quantum dots and gaining individual control over them, we look forward to entangling multiple of these single photon emitters, towards the preparation of a photonic cluster state. Such complex entangled states could be used as a resource for what is known as measurement-based quantum computing.
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