Julian Schmitt’s research is focused on experimental quantum many-body physics with photons and atoms, to address fundamental questions from topological physics over condensed matter to secure quantum communication. By exploring the novel field of optical quantum gases, Julian’s research provides general answers to open questions in physics, which revolve around the realization of room-temperature superfluidity or topological states, which are regarded as a key resource for robust quantum technology. In his previous work, Julian has contributed to landmark achievements in quantum physics, including the first observation of Bose-Einstein condensation of photons or the universal jump in topological BKT superfluidity.