Tricks for FTIR photoluminescence using double modulation or step scan mode toward MIR and beyond

A simple review of Fourier transform infrared spectroscopy and a historical overview of the development of emission spectroscopy, especially the photoluminescence characterization adopting double modulation or the step scan mode toward the mid-infrared band and beyond, are presented. Based on the retrospection and our experiences, detailed considerations and trade-offs on the configuration of the photoluminescence characterization system, as well as parameter setting tricks and operation skills of different modes, are expounded. Keeping in mind the above background, the merits of double modulation and step scan modes in Fourier transform infrared spectroscopy photoluminescence toward the mid-infrared band and beyond, in conjunction with selecting strategies of the two modes, are discussed. It is shown that the double modulation mode has the advantage of operation convenience at the cost of a slightly higher noise level, while the step scan mode possesses better data quality but with a significantly longer operation time and inconvenience. The combination of the two in modern research grade Fourier transform infrared spectrometers provides a unified solution.