Time-resolved photoluminescence spectroscopy
Time-resolved photoluminescence spectroscopy (TRPL) is an extension to normal spectroscopy in which a short laser pulse is used for excitation, and a fast detector is used to determine the emission of a material as a function of time after excitation. This technique can be used to measure material quality (higher quality material tends to have a longer emission time), to help identify spectral emissions with specific emissive states or to study energy transfer from one component to another in mixed systems, like solar cells.
The EME system is based around the time-correlated single photon counting (TCSPC) technique, using a Picoharp 300 timing unit. The system is equipped with a 522nm and 1044nm laser and a silicon detector, covering the 200nm to 1050nm emission range. A time-resolution of around 50ps with a maximum range of 50ns is achievable. A microscope equipped with either motorised positioning (200nm resolution) or a low temperature stage (~4K) is also available to be used with this system.