Fig. 3: Compensation and carrier traps in doped heterostructures.

a Injection-dependent donor-acceptor pair (DAP) spectral shifts at 5 K. Lines are fits to the model from ref. 45. Insets show spectra measured with the lowest (black) and the highest (red) injection. b Defect energy diagrams. Values are also listed in Table 1. c Temperature-dependent PL emission spectra used to determine D1/D2 activation energies. Excitation fluence was the same and intensities can be compared. (Gray shaded areas indicate scattering from glass substrates).