Temperature dependence of Stokes shift in In_xGa_1-xN/GaN multiple quantum wells

Luminescence properties of InxGa1-xN/GaN multiple quantum wells (MQWs) have been studied by means of photoluminescence excitation (PLE) spectroscopy. The clear peak due to the absorption of InxGa1-xN quantum wells was observed in the PLE spectrum of the MQW sample with x < 0.01 at 4 K, and the Stokes shift was estimated to be 63 meV. It was found that the Stokes shift was independent of temperature up to 300 K. This result suggests that the large Stokes shift cannot be explained only by the effect of carrier localization due to compositional fluctuation.

In_xGa_1-xN

GaN multiple quantum wells

photoluminescence excitation

Stokes shift

compositional fluctuation

localization