Search

Intraband luminescence (IBL) is a prompt emission originating from the radiative intraband transitions of charge carriers during thermalisation. Despite its low intensity, IBL can hopefully enhance scintillation time resolution, for instance, in positron emission tomography. The continuous and structureless spectrum of IBL spans over the whole transparency region of a material. Exploiting a wide spectral sensitivity range of our instrumentation (0.77–10.6 eV), we have discovered a strong rise of IBL spectral yield in the NIR region in all studied compounds, which could not be explained within the available theoretical models of IBL. We have developed a new model attributing the NIR rise of the IBL spectrum to the phonon-assisted electron transitions within a single parabolic energy band, which yields a fair correspondence to our experimental data. [ABSTRACT FROM AUTHOR]

In a combined experimental and numerical investigation, we present the effects of trap-assisted tunneling on the sub-threshold forward bias characteristics of a blue InGaN/GaN single-quantum-well LED test structure grown on a SiC substrate. The different role of donor- and acceptor-like traps has been studied, for the information it can provide on the role played by point defects. Using the energy Et and trap density Nt as the only tunneling-related fitting parameters, the behavior of the measured I( V) curves is well reproduced by our model over a wide current and temperature range. The very good agreement between simulations and experiments suggests that trap-assisted forward tunneling is one of the most relevant contributions to the current flow below the optical turn-on of the diode. [ABSTRACT FROM AUTHOR]