Advancements in the generation of photon pairs using quantum dots and thin film spontaneous parametric down conversion source

by Charlie James Stalker (Stockholm University)

Tuesday 1 Dec 2026, 14:00 → 16:00 Europe/Stockholm

AlbaNova A3:1003 - Styrelserum/KOMKO (AlbaNova Main Building)

The generation of photon pairs is a critical process in most quantum communication protocols and a promising resource for quantum computing. In this thesis we showcase a thin film of rhombohedral tungsten disulfide (3R-WS2) as a potential small form factor source of high fidelity Bell states. 3R-WS2 has extremely high χ(2) non-linearities upwards of 10× more than cutting edge lithium niobate crystals. This allows for reasonably high pair-generation rate even in sub micron crystal lengths. The non-linear tensor of this material allows for the generation of maximally entangled states by simply pumping with any linear polarization, allowing a much simpler down-conversion source ofentangled photons. We also touch on two results in the field of quantum dots;one focuses on the relationship of exciton and biexciton coherence times in Hong-Ou-Mandel interference measurements for varying rates of pure dephasing, the other introduces a computational super-resolution technique designed to simplify one of the steps in quantum dot source fabrication