Interpretation of the "S-shaped" temperature dependence of luminescent peaks from semiconductors

The ``S-shape'' (decrease-increase-decrease) temperature dependence of luminescence peak shift from semiconductors is considered. A luminescence model for localized state ensemble was employed to interpret this anomalous temperature dependence of emission peak. Excellent agreement between the theoretical calculation and the experiments was achieved over the whole studied temperature region. The physical origin of the ``S-shaped'' shift is revealed.