Ali Oguz Er - Various Uses of Lasers in Thin Film Deposition, Nanoscale Heat Transport in Solids, Photodeactivation of Pathogenic Bacteria and Viruses in Human Blood, and Quantum Control Experiments

Speaker: Ali Oguz Er, Applied Physics Institute, Western Kentucky University

Abstract: Various uses of lasers will be presented. A review of the nucleation and growth studies by Pulsed Laser Deposition (PLD) using in-situ reflection high energy electron diffraction (RHEED), atomic force microscopy (AFM), and scanning tunneling microscopy (STM) will be given.

Nanoscale heat transport across the Cu/Ag(111) interface and the transient structural disorder in Ag(111) crystal after excitation of the 18 nm copper with femtosecond pulses was studied by means of time resolved X-ray diffraction. The lattice disorder after UV irradiation is detected by changes in peak shift and broadening of the XRD rocking curve. We have observed blast force and pressure wave propagation.

The photo-inactivation rate of bacteria by methylene blue, MB, was found to be significantly lower in plasma than in water, saline, and PBS solutions. The spectroscopic data and ultrafast time resolved transient spectra and kinetics presented, show that methylene blue under continuous wave red light (~660 nm) photo-bleaches faster and to a larger degree in plasma and the MB excited singlet and triplet state populations in plasma are much lower in plasma than in water and PBS solutions.

Lastly, ongoing quantum control experiments by using femtosecond lasers in nonlinear media at Princeton University will be presented.