We report on an experimental study of the self-frequency detuning in wave mixing oscillators with the photorefractive barium titanate crystal. We show its dependence on a dc electric field on the crystal, optical phases in the oscillator cavity, and light intensity in the crystal. This resolves many aspects of previously observed and unexplained self-frequency detuning effects with similar osci...

Optical processing via high-pass filtering is a well-established means of enhancing image contrast. However, this procedure is energetically inefficient, because the power associated with the low-spatial-frequency components of the image is ordinarily discarded. We demonstrate a means of performing contrast enhancement in an energy efficient manner, by recycling the optical power ordinarily dis...

Nanocomposites with nanofillers of reactive montmorillonite covalently-bonded with barium titanate G. Polizos, V. Tomer, E. Manias, and C. A. Randall Polymer Nanostructures Laboratory, Center for the Study of Polymeric Systems (CSPS) and Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA Center of Dielectric Studies (CDS)...

stoichiometric tetragonal bal-xsrxtio3 (x = 0.23) nanopowders were prepared by stearic acid gel(sag) method using barium stearate, strontium stearate, tetrabutyl titanate as ba, sr, ti sourcesand stearic acid as complexing reagent. thermal analysis including differential thermogravimetric(dtg) and tg, fourier transform infrared spectrometry (ftir), x-ray diffraction (xrd) andtransmission electr...

Effects of montmorillonite and barium titanate nanofillers V. Tomer, G. Polizos, E. Manias, and C. A. Randall Department of Materials Science and Engineering, Materials Research Laboratory, Center of Dielectric Studies (CDS), The Pennsylvania State University, University Park, Pennsylvania 16802, USA Department of Materials Science and Engineering, Polymer Nanostructures Laboratory, Center for ...

The effect of titanium dioxide as a semiconductive additive and barium titanate as a highly polar additive on the d.c. transient currents in low density polyethylene is investigated. Experiments were made using thick specimens under high electric field ( > 25 x 106 V/m) and constant temperature of 40OC. Results indicate that the incorporation of the foresaid additives has a remarkable effect on...