Synchrotron–laser pump–probe luminescence spectroscopy: correlation of electronic defect states with x-ray absorption in wide-gap solids

The potential for synchrotron–laser pump–probe luminescence measurements to provide a direct link between the chemical/structural properties of light emitting wide band-gap solids and optically active electronic trapping states is evaluated. Initial results are presented that demonstrate the various excitation and relaxation processes involved, whereby the synchrotron pump provides the chemical/structural information, and the laser probes both radiative and non-radiative electronic trapping states. The examples described here demonstrate that the laser probe may quench, be neutral, or enhance the synchrotron-pumped luminescence of the wide band-gap materials boron nitride, SiO 2 and Na 0.7 Ca 0.3 Al 1.3 Si 2.7 O 8 , respectively. Consideration is given to the potential of the method to provide a general route to the analysis of single components in heterogeneous systems.