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arXiv · 1307.3636

Stimulated emission from ZnO thin films with high optical gain and low loss

A-S. Gadallah·K. Nomenyo·C. Couteau·D. J. Rogers·G. Lérondel
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Abstract

Stimulated surface- and edge-emission were investigated for ZnO thin films grown epitaxially by pulsed laser deposition. The lasing threshold was 0.32 MW/cm2 for surface pumping and 0.5 MW/cm2 for edge pumping, which is significantly lower than thresholds observed previously. A modified variable stripe length method was used to measure the gain, which was 1369 cm-1 for N-band emission. Losses were measured using the shifting excitation spot method and values of 6.2 cm-1 and 6.3 cm-1 were found for the N-band and P-band, respectively. The measured gain and loss were the highest and lowest (respectively) ever reported for ZnO films.

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A-S. Gadallah, K. Nomenyo, C. Couteau, D. J. Rogers, G. Lérondel. 2013-07-13. Stimulated emission from ZnO thin films with high optical gain and low loss. https://doi.org/10.1063/1.4803081

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