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arXiv · 1306.3023

Waveguiding-assisted random lasing in epitaxial ZnO thin film

P. -H. Dupont·C. Couteau·D. J. Rogers·F. Hosseini Téhérani·G. Lérondel
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Abstract

Zinc Oxide thin films were grown on c-sapphire substrates using pulsed laser deposition. Pump power dependence of surface emission spectra, acquired using a quadrupled 266 nm laser, revealed room temperature stimulated emission (threshold of 900 kW/cm2). Time dependent spectral analysis plus gain measurements of single-shot, side-emission, spectra pumped with a nitrogen laser revealed random lasing indicative of the presence of self-forming laser cavities. It is suggested that random lasing in an epitaxial system rather than a 3-dimensional configuration of disordered scattering elements, was due to waveguiding in the film. Waveguiding causes light to be amplified within randomly-formed closed-loops acting as lasing cavities.

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P. -H. Dupont, C. Couteau, D. J. Rogers, F. Hosseini Téhérani, G. Lérondel. 2013-06-13. Waveguiding-assisted random lasing in epitaxial ZnO thin film. https://doi.org/10.1063/1.3527087

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