A theoretical description of light emission, propagation, and re-absorption in semiconductor multilayer stacks is derived based on the transverse Green’s function of the electromagnetic field in the presence of a complex dielectric. The framework obtained is shown to reproduce the generalized Kirchhoff relations between the luminescent emission from metal halide perovskite slabs under uniform excitation and the slab absorptance of light with an arbitrary angle of incidence. Finally, consistent treatment of re-absorption provides the local rate of secondary photogeneration required for the consideration of photon recycling in an optoelectronic device simulator that includes the effects of charge transport.

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