Quadratic light-matter interactions are nonlinear couplings such that quantum emitters interact with photonic or phononic modes exclusively via the exchange of excitation pairs. Implementable with atomic and solid-state systems. these couplings lead to a plethora of phenomena that have been characterized in the context of cavity QED. where quantum emitters interact with localized boso... https://www.chiggate.com/earthbath-facial-wipes-25ct-fashion/