Researchers stabilize interference of two photons in optical chips using topological wave propagation

https://phys.org/news/2024-06-stabilize-photon-optical-chips-topological.html

"combine topologically robust light propagation with photon pair interference... optical element topological protection... photons pairs perceive waveguide structure as twisted, causing them to link up, photons passing through waveguide separately only experience conventional flat surface, a topological difference... waveguide system deformable without impact on quantum interference...numerous possibilities for constructing topological systems for light. The symbiosis with quantum light is just the beginning"