Stimulated dipole–dipole interaction: A highly efficient mechanism for amplifying light-generated effects

A concept termed “stimulated dipole–dipole interaction” as a framework is proposed to describe coherence-enhanced light–matter interactions. Unlike conventional dipole–dipole interactions, excitation-induced dipoles, generated through external perturbations, coherently stimulate and couple with each other, leading to reinforced transition pathways and modified physical characteristics. Theoretically, the phenomenon of stimulated dipole–dipole interaction can be well understood and calculated based on the additional interference terms between transition dipole matrix elements of perturbed Hamiltonians in Fermi’s golden rule, where coherent coupling between excitation-induced and intrinsic dipoles alters the overall transition probability. This framework can be applied to many platforms, including wrinkled graphene, quantum dots, plasmonic dipoles, exciton–polaritons in stacked two-dimensional materials, and electric and magnetic dipoles in spin resonance, offering a versatile approach for engineering light–matter interactions. It is pointed out that the underlying mechanism of the originally proposed stimulated emission can also be understood well based on stimulated dipole–dipole interaction. Therefore, the proposed stimulated dipole–dipole interaction paves a milestone to advance the further exploration of not-yet realized quantum optics phenomena.