6533b82cfe1ef96bd128f46d

RESEARCH PRODUCT

Investigation of nitrogen-related acceptor centers in indium selenide by means of photoluminescence: Determination of the hole effective mass

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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-\ensuremath{\mu}s lifetime) with LO-phonon replica. An ionization energy of 65.5 meV is proposed for the nitrogen-related acceptor. A long-lived (18 \ensuremath{\mu}s) 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 ${\mathrm{m}}_{\mathrm{h}\mathrm{\ensuremath{\perp}}}^{\mathrm{*}}$=(0.73\ifmmode\pm\else\textpm\fi{}0.09)${\mathrm{m}}_{0}$ and ${\mathrm{m}}_{\mathrm{h}\mathrm{\ensuremath{\Vert}}}^{\mathrm{*}}$=(0.17\ifmmode\pm\else\textpm\fi{}0.03)${\mathrm{m}}_{0}$.