Interband thermoluminescence of semiconductors and semiconductor nanocrystals in the near-infrared

The thermally excited luminescence of undoped semiconductors and semiconductor nanocrystals near the band gap is explored by a simple and unconventional experimental technique. Luminescence spectra are obtained at ambient conditions after slightly heating the samples to approximately 100 °C without using any additional electronic or optical means of excitation. In our investigations, bulk GaAs, bulk InP and semiconductor doped glasses are studied. We show that absorption properties and band gap positions obtained directly from emission spectra not only correspond well to those obtained from transmission measurements, but also yield additional information about the role of defects giving rise to emission from within the band gap.