In this work we report on steady-state and time-resolved photoluminescence (PL) measurements in nitrogen-doped p-type indium selenide in the 33–210-K temperature range. In samples with low nitrogen concentration the photoluminescence spectrum consists of exciton-related peaks and a band-to-acceptor recombination peak (2.1-μs lifetime) with LO-phonon replica. An ionization energy of 65.5 meV is proposed for the nitrogen-related acceptor. A long-lived (18 μs) component, which consists of an asymmetric broadband centered around the acceptor peak, has been also detected by means of time-resolved PL. Samples with a higher nitrogen concentration show a PL spectrum that mainly consists of the asymmetric long-lived broadband that can be associated to a complex center. The asymmetric shape of this band is quantitatively accounted for in the framework of the configuration coordinate model for complex centers. Under the assumption that the nitrogen-related acceptor is shallow, the Gerlach-Pollman theory allows an estimate of the hole's effective masses, yielding ${\mathrm{m}}_{\mathrm{h}\mathrm{\perp }}^{\mathrm{*}}$=(0.73±0.09)${\mathrm{m}}_0$ and ${\mathrm{m}}_{\mathrm{h}\mathrm{\Vert }}^{\mathrm{*}}$=(0.17±0.03)${\mathrm{m}}_0$.

DOI:https://doi.org/10.1103/PhysRevB.55.6981