Search Results - "VAN KEULS, F. W."

Improvement in electrical characteristics of graded manganese doped barium strontium titanate thin films by Jain, M., Majumder, S. B., Katiyar, R. S., Miranda, F. A., Van Keuls, F. W.

“…Highly (100) textured graded manganese (Mn) doped Ba0.5Sr0.5TiO3 [BST (50/50)] thin films were deposited on lanthanum aluminate substrates using sol-gel…”
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Epitaxial growth of dielectric Ba0.6Sr0.4TiO3 thin film on MgO for room temperature microwave phase shifters by Chen, C. L., Shen, J., Chen, S. Y., Luo, G. P., Chu, C. W., Miranda, F. A., Van Keuls, F. W., Jiang, J. C., Meletis, E. I., Chang, H. Y.

“…Dielectric Ba0.6Sr0.4TiO3 thin films were epitaxially grown on (001) MgO by using pulsed laser ablation. Microstructure studies from x-ray diffraction and…”
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Epitaxial ferroelectric Ba0.5Sr0.5TiO3 thin films for room-temperature tunable element applications by Chen, C. L., Feng, H. H., Zhang, Z., Brazdeikis, A., Huang, Z. J., Chu, W. K., Chu, C. W., Miranda, F. A., Van Keuls, F. W., Romanofsky, R. R., Liou, Y.

“…Perovskite Ba0.5Sr0.5TiO3 thin films have been synthesized on (001) LaAlO3 substrates by pulsed laser ablation. Extensive x-ray diffraction, rocking curve, and…”
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Design and development of ferroelectric tunable HTS microstrip filters for Ku- and K-band applications by Subramanyam, G, Van Keuls, F.W, Miranda, F.A, Romanofsky, R.R, Warner, J.D

“…In the past few years, our group has designed, fabricated and tested several ferroelectric tunable components, in collaboration with NASA Glenn Research…”
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A K-band (HTS,gold)/ferroelectric thin film/dielectric diplexer for a discriminator-locked tunable oscillator by Miranda, F.A., Subramanyam, G., Van Keuls, F.W., Romanofsky, R.R.

“…The performance of a K-band conductor/ferroelectric thin film/dielectric tunable diplexer that is being developed as a critical part of a discriminator-locked…”
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Structural and dielectric properties of epitaxial Ba1−xSrxTiO3/Bi4Ti3O12/ZrO2 heterostructures grown on silicon by Canedy, C. L., Aggarwal, S., Li, Hao, Venkatesan, T., Ramesh, R., Van Keuls, F. W., Romanofsky, R. R., Miranda, F. A.

“…We report on the dielectric properties of an epitaxial heterostructure comprised of Ba1−xSrxTiO3, Bi4Ti3O12, and (ZrO2)0.91(Y2O3)0.09 grown on silicon…”
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Dielectric Properties and Leakage Current Characteristics of Sol-Gel Derived (Ba0.5Sr0.5)TiO3:MgTiO3 Thin Film Composites by Jain, M., Majumder, S. B., Yuzyuk, Yu, Katiyar, R. S., Bhalla, A. S., Miranda, F. A., Van Keuls, F. W.

“…(Ba1-xSrx)TiO3 (BST) is a suitable material for microelectronic device applications due to its high response of the dielectric permittivity to an applied…”
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COMPARATIVE STUDIES OF FERROELECTRIC THIN FILMS FOR HIGH FREQUENCY PHASE SHIFTER APPLICATIONS by KATIYAR, R. S., JAIN, M., KARAN, N. K., BHALLA, A. S., MIRANDA, F. A., VAN KEULS, F. W.

“…We have synthesized P 0.3 Sr 0.7 TiO 3 (PST30) thin films on platinum and lanthanum aluminate sustrates using chemical solution deposition technique. The films…”
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Comparison of the experimental performance of ferroelectric CPW circuits with method-of-moment simulations and conformal mapping analysis by Van Keuls, F. W., Chevalier, C. T., Miranda, F. A., Carlson, C. M., Rivkin, T. V., Parilla, P. A., Perkins, J. D., Ginley, D. S.

“…Experimental measurements of coplanar waveguide circuits atop thin films of ferroelectric BaxSr1−xTiO3 (BST) were made as a function of dc bias from 0 to 200 V…”
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Tunable microwave components for Ku-and K-band satellite communications by Miranda, F. A., Keuls, F. W. Van, Romanofsky, R. R., Subramanyam, G.

“…The use of conductor/ferroelectric/dielectric thin film multilayer structures for frequency and phase agile components at frequencies at and above the Ku-band…”
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Investigations of sol-gel-derived highly (100)-oriented Ba0.5Sr0.5TiO3:MgO composite thin films for phase-shifter applications by JAIN, M, MAJUMDER, S. B, KATIYAR, R. S, BHALLA, A. S, MIRANDA, F. A, VAN KEULS, F. W

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A K-band-frequency agile microstrip bandpass filter using a thin-film HTS/ferroelectric/dielectric multilayer configuration by Subramanyam, G., Van Keuls, F.W., Miranda, F.A.

“…In this paper, we report on YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) thin-film/SrTiO/sub 3/ (STO) thin-film K-band tunable bandpass filters on LaAlO/sub…”
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Synthesis and Characterization of Nanostructured BSTO Thin-Films for Microwave Applications by Riehl, Bonnie, Subramanyam, Guru, Biggers, Rand, Campbell, Angela, Van Keuls, Fred W., Miranda, Felix A., Tomlin, David

“…Nanophase synthesis of ferroelectric thin-films of Ba 0.6 Sr 0.4 TiO 3 (BSTO) was studied systematically for applications in tunable microwave components…”
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Tailoring of BST and MgO Layers for Phase Shifter Applications by JAIN, M., MAJUMDER, S. B., KATIYAR, R. S., BHALLA, A. S., MIRANDA, F. A., VAN KEULS, F. W.

“…Sol-gel technique has been utilized to deposit heterostructured Ba 0.5 Sr 0.5 TiO 3 :MgO (BST:MgO) films with different BST/MgO layer sequences and thicknesses…”
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A Large Scale Production Test of Thin Film BaxSr1-xTiO3 Microwave Phase Shifters Fabricated on LaAlO3 Substrates by Van Keuls, F W, Varaljay, N C, Mueller, C H, Alterovitz, S A, Miranda, F A, Romanofsky, R R

“…Many individual tunable ferroelectric-based microwave components have demonstrated excellent performance. However data on the production of many identical…”
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A ferroelectric tunable microstrip Lange coupler for K-band applications by Subramanyam, G., Miranda, F.A., Romanofsky, R.R., Van Keuls, F.W., Canedy, C.L., Aggarval, S., Venkatesan, T., Ramesh, R.

“…We report on the modeled and experimentally verified performance of a gold/Ba/sub 0.6/Sr/sub 0.4/TiO/sub 3/ (BSTO) ferroelectric/magnesium oxide (MgO)…”
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Experimental Evidence for Correlated Hopping in Two Dimensions by Van Keuls, F. W., Dahm, A. J.

“…The ratio C2/β, where C and β are constants associated with variable‐range hopping, is determined by requiring a smooth variation of the localization length…”
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Screening of the Coulomb gap by Hu, X.L., Van Keuls, F.W., Carmi, Y., Jiang, H.W., Dahm, A.J.

“…Data from resistivity measurements are presented which confirm a Coulomb gap in the density of states in two-dimensional variable-range hopping. For large…”
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Design and development of ferroelectric tunable microwave components for Kuand K-band satellite communication systems by Miranda, F.A., Subramanyam, G., van Keuls, F.W., Romanofsky, R.R., Warner, J.D., Mueller, C.H.

“…Integration of a high-temperature superconductor with a nonlinear dielectric ferroelectric such as strontium titanate, i.e., SrTiO/sub 2/ (STO), has created a…”
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Current status of thin film (Ba,Sr)TiO3 tenable microwave components for rf communications by Van Keuls, F. W., Romanofsky, R. R., Mueller, C. H., Warner, J. D., Canedy, C. L., Ramesh, R., Miranda, F. A.

“…The performance of proof-of-concept ferroelectric microwave devices has been moving steadily closer to the level needed for satellite and other rf…”
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