An improved experimental determination of external photoluminescence quantum efficiency

The external photoluminescence quantum yield of, for example, thin film semiconductors can be conveniently determined using the improved integrating‐sphere method (see Figure) presented here. Spectrally resolved detection allows the excitation source and the emission to be distinguished. The method will be particularly useful for samples with small Stocks' shifts or low photoluminescence quantum yields or for highly scattering samples. Fig