Deterministic sources of entangled photons, based on either real or “artificial” atoms, have garnered significant attention due to their potential applications in quantum science and technology. In these systems, polarization entanglement arises from the conservation of total angular momentum during a radiative cascade. According to theory, the degree of entanglement reaches its maximum only when light is collected along a specific direction, and there must be a correlation to the emission angle. This fundamental effect was previously believed to be negligible in simple atomic systems, which led to it being largely overlooked. However, in a recent study published in Nature Communications, the Nanophotonics group led by Prof. Rinaldo Trotta – in a joint effort with scientists from Austria and Germany – reported for the first time the observation of this effect in quantum dots within a nanophotonic cavity. The results provide a novel insight into cascaded emission in atomic systems.