Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1555150 | Superlattices and Microstructures | 2007 | 6 Pages |
Abstract
We have studied temperature dependent photoluminescence (PL) from ZnO Multiple Quantum Wells (MQWs) of different well layer thicknesses in the range â¼1-4Â nm grown on (0001) sapphire by a novel in-house developed buffer assisted pulsed laser deposition. At 10Â K the PL peak shifted toward blue with decreasing well layer thickness and at constant well layer thickness the PL peak shifted towards red with increasing temperature. To the best of our knowledge we have observed for the first time an efficient room temperature (RT) PL emanating from such MQWs. The red shift of the PL peak with increasing temperature has been found to be due to the band gap shrinkage in accordance with the Varshni's empirical relation. The spectral linewidth was found to increase with increasing temperature due to the scattering of excitons with acoustic and optical phonons in different temperature regimes. Both at RT and at 10Â K the PL peak shifted with respect to the well layer thickness in the range of â¼3.35-â¼3.68Â eV with decreasing thickness in agreement with the calculated values.
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
P. Misra, T.K. Sharma, L.M. Kukreja,