Double modulation techniques in Fourier Transform infrared photoluminescence
Doppelmodulationsverfahren in der Infrarot-Photolumineszenz-Fourierspektroskopie
FT photoluminescence is a powerful tool to study mid infrared emission. However, problems may arise from thermal background radiation. A new phase locked modulation technique is presented and will be compared with existing double modulation (lock-in) techniques. The basic idea in our new technique is to apply a phase sensitive excitation of the luminescence instead of phase sensitive detection to separate the luminescence spectra from dominant thermal background radiation. As examples, luminescence of ZnS:Ni and Hg0.73Cd0.27Te are studied.