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Photoluminescence spectroscopy is a simple and powerful characterization technique to determine material properties and dynamic effects in metal–halide perovskite optoelectronic systems. However, self‐absorption and thin film cavity effects, amplified due to their high refractive indices, can have a significant impact on spectral lineshapes, affecting the inferences drawn from such characterization. In this work, key variables extrinsic to the perovskite material influencing the photoluminescence spectrum of perovskite thin films are identified and an optical model to account for these factors is proposed. The model is used to extract the intrinsic spectrum of a film using complex refractive indices and film thickness as input variables. Lastly, the use of the model is extended to multilayer systems to demonstrate its applicability to complex device‐relevant stacks. [ABSTRACT FROM AUTHOR]

Accurate determination of the photoluminescence (PL) spectrum of molecules is crucial in many areas including molecular diagnostics, genome analysis, and organic electronics. However, interpretation of experimental spectra from thin films can be complicated by phenomena extrinsic to the site of photon emission such as optical interference and self‐absorption. In this study, the alteration of fluorescence spectral lineshape is modeled from a thin film due to extrinsic factors as function of film thickness, incident angle, bandgap, and Stokes shift. The method is experimentally verified for thin (<400 nm) layers of molecular semiconductors on quartz substrates. Finally, a chart is provided for estimating the magnitude of the error due to extrinsic factors in the bandshape of fluorescence spectra from thin films. This demonstrates that the 0‐0/0‐1 intensity ratio, an indicator of the nature of excitonic coupling, is especially sensitive to possibly unconsidered influence from extrinsic effects. [ABSTRACT FROM AUTHOR]

We present a versatile, simple, and rapid numerical technique based on thin-film optics for analyzing distributed Bragg reflectors composed of any material system. This technique is an alternative to the commonly used coupled-mode theories or matrix methods. Simulation results agree with those obtained using conventional matrix methods, and with the measured reflectivity of an MBE-grown III–V DBR. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 11–15, 1999. [ABSTRACT FROM AUTHOR]