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Abdalla M. Darwish

Abdalla M. Darwish

Dillard University, USA

Title: Double pulse laser deposition of polymer nanocomposite films for optical sensors and light emitting applications

Biography

Dr. Abdalla Darwish obtained his BS in Nuclear Engineering from University of Alexandria, MS in Solid State Physics and PhD in optics and laser physics from the University of Alabama in Tuscaloosa. He has been a Dillard University faculty member for sixteen years and has served the university in numerous administrative roles, including chair of the physics department, chair of the School of STEM, interim dean of the College of Arts and Sciences, and Associate Vice President for Academic Affairs. He was recently named Dillard University’s first Presidential Professor.

Abstract

The objective is to determine the visibility of creating operationally polymer nanocomposite films for sensor and light emitting applications using the innovative modified double pulse laser deposition (DPLD) for host and dopant. The existing pulse laser deposition vacuum chamber has been modified to accommodate two laser beams of contrasting wavelengths for the situ ablation of two targets: a polymer host and a rare Earth-based highly efficient up conversion emitting inorganic dopant. Nanocomposite films of acrylic polymer and of the compounds of the rare Earth elements were fabricated by the proposed method with near-infrared (NIR) laser radiation (1064-nm wavelength) ablating the polymer targets and visible radiation (532-nm wavelength) ablating the inorganic targets. The devised nanocomposite films were characterized using X-ray diffraction (XRD), atomic force microscopy (AFM), ultra-violet visible optical absorption spectroscopy, and reflected high energy electron diffraction (RHEED). It was revealed that the produced polymer nanocomposite films maintained the crystalline structure and the up conversion fluorescence properties of the initial rare Earth-compounds mainly due to the preferred control of the deposition process of the materials with essentially different properties. The prospective method can be potentially used for making a wide variety of composite films.