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Full-Text Articles in Engineering
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Graduate Theses and Dissertations
Growing population and climate change inevitably requires longstanding dependency on sustainable sources of energy that are conducive to ecological balance, economies of scale and reduction of waste heat. Plasmonic-photonic systems are at the forefront of offering a promising path towards efficient light harvesting for enhanced optoelectronics, sensing, and chemical separations. Two-dimensional (2-D) metamaterial arrays of plasmonic nanoparticles arranged in polymer lattices developed herein support thermoplasmonic heating at off-resonances (near infrared, NIR) in addition to regular plasmonic resonances (visible), which extends their applicability compared to random dispersions. Especially, thermal responses of 2-D arrays at coupled lattice resonance (CLR) wavelengths were comparable …
Applications Of High Throughput Screening Tools For Thermoelectric Materials, W. Wong-Ng, H. Joress, J. Martin, Y. Yan, M. Otani, E. Thomas, M. Green, Jason Hattrick-Simpers
Applications Of High Throughput Screening Tools For Thermoelectric Materials, W. Wong-Ng, H. Joress, J. Martin, Y. Yan, M. Otani, E. Thomas, M. Green, Jason Hattrick-Simpers
Jason R. Hattrick-Simpers
No abstract provided.
The Effect Of Copt Crystallinity And Grain Texturing On Properties Of Exchange-Coupled Fe/Copt Systems, H. Oguchi, A. Zambano, M. Yu, Jason Hattrick-Simpers, D. Banerjee, Y. Liu, Z. Wang, J. Liu, S. Lofland, D. Josell, I. Takeuchi
The Effect Of Copt Crystallinity And Grain Texturing On Properties Of Exchange-Coupled Fe/Copt Systems, H. Oguchi, A. Zambano, M. Yu, Jason Hattrick-Simpers, D. Banerjee, Y. Liu, Z. Wang, J. Liu, S. Lofland, D. Josell, I. Takeuchi
Jason R. Hattrick-Simpers
The effect of the crystallinity and the grain texturing of CoPt hard layers on exchange coupled Fe/CoPt soft/hard magnetic systems was studied using gradient thickness multilayer thin films. We have studied the hard layer structures by transmission electron microscopy and x-ray diffraction, and characterized the exchange coupling interaction through magnetization loops obtained by the magneto-optical Kerr effect measurement. We found that exchange coupling strongly depends on the crystalline characteristics of the CoPt hard layer. There is correlation between the mixture of different grain orientations of the CoPt hard layer and coupling efficiency. In particular, interlayer coupling is enhanced when there …
Combinatorial Study Of Ni-Ti-Pt Ternary Metal Gate Electrodes On Hfo2 For The Advanced Gate Stack, K.-S. Chang, M. Green, J. Suehle, E. Vogel, H. Xiong, Jason Hattrick-Simpers, I. Takeuchi, O. Famodu, K. Ohmori, P. Ahmet, T. Chikyow, P. Majhi, B.-H. Lee, M. Gardner
Combinatorial Study Of Ni-Ti-Pt Ternary Metal Gate Electrodes On Hfo2 For The Advanced Gate Stack, K.-S. Chang, M. Green, J. Suehle, E. Vogel, H. Xiong, Jason Hattrick-Simpers, I. Takeuchi, O. Famodu, K. Ohmori, P. Ahmet, T. Chikyow, P. Majhi, B.-H. Lee, M. Gardner
Jason R. Hattrick-Simpers
The authors have fabricated combinatorial Ni–Ti–Pt ternary metal gate thin film libraries on HfO2 using magnetron co-sputtering to investigate flatband voltage shift (ΔVfb) , work function (Φm) , and leakage current density (JL) variations. A more negative ΔVfb is observed close to the Ti-rich corner than at the Ni- and Pt-rich corners, implying smaller Φm near the Ti-rich corners and higher Φm near the Ni- and Pt-rich corners. In addition, measured JL values can be explained consistently with the observed Φm variations. Combinatorial methodologies prove to be useful in surveying the large compositional space of ternary alloymetal gate electrode systems.
Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. Wang, J. Liu, S. Lofland, Somdev Tyagi, J. Freeland, D. Giubertoni, M. Bersani, M. Anderle
Interphase Exchange Coupling In Fe/Sm-Co Bilayers With Gradient Fe Thickness, Ming-Hui Yu, Jason Hattrick-Simpers, Ichiro Takeuchi, Jing Li, Z. Wang, J. Liu, S. Lofland, Somdev Tyagi, J. Freeland, D. Giubertoni, M. Bersani, M. Anderle
Jason R. Hattrick-Simpers
We have fabricated Fe∕Sm–Co bilayers with gradient Fe thicknesses in order to systematically study the dependence of exchange coupling on the thickness of the Fe layer. The Fe layer was deposited at two different temperatures (150 and 300°C) to study the effect of deposition temperature on the exchange coupling. Magneto-optical Kerr effect and x-ray magnetic circular dichroism (XMCD) have been employed as nondestructive rapid characterization tools to map the magnetic properties of the gradient samples. Systematic enhancement in exchange coupling between the soft layer and the hard layer is observed as the soft layer thickness is decreased. Separate exchange couplings …
High-Throughput Screening Of Shape Memory Alloy Thin-Film Spreads Using Nanoindentation, Arpit Dwivedi, Thomas Wyrobek, Oden Warren, Jason Hattrick-Simpers, Olubenga Famodu, Ichiro Takeuchi
High-Throughput Screening Of Shape Memory Alloy Thin-Film Spreads Using Nanoindentation, Arpit Dwivedi, Thomas Wyrobek, Oden Warren, Jason Hattrick-Simpers, Olubenga Famodu, Ichiro Takeuchi
Jason R. Hattrick-Simpers
We have demonstrated the utility of nanoindentation as a rapid characterization tool for mapping shape memoryalloy compositions in combinatorial thin-film libraries. Nanoindentation was performed on Ni–Mn–Al ternary composition spreads. The indentation hardness and the reduced elastic modulus were mapped across a large fraction of the ternary phase diagram. The large shape memoryalloy composition region, located around the Heusler composition (Ni2MnAl), was found to display significant departure in these mechanical properties from the rest of the composition spread. In particular, the modulus and the hardness values are lower for the martensite region than those of the rest of the phase diagram.
A Semi-Empirical Model For Tilted-Gun Planar Magnetron Sputtering Accounting For Chimney Shadowing, Johnathan Bunn, C. Metting, Jason Hattrick-Simpers
A Semi-Empirical Model For Tilted-Gun Planar Magnetron Sputtering Accounting For Chimney Shadowing, Johnathan Bunn, C. Metting, Jason Hattrick-Simpers
Jason R. Hattrick-Simpers
No abstract provided.
Recent Developments In Thermoelectric Metrology At Nist, W. Wong-Ng, J. Martin, E. Thomas, M. Otani, N. Lowhorn, M. Green, G. Liu, Y. Yan, Jason Hattrick-Simpers, T. Tran
Recent Developments In Thermoelectric Metrology At Nist, W. Wong-Ng, J. Martin, E. Thomas, M. Otani, N. Lowhorn, M. Green, G. Liu, Y. Yan, Jason Hattrick-Simpers, T. Tran
Jason R. Hattrick-Simpers
No abstract provided.
Exploration Of Magnetoelectric Thin-Film Sensors Using Supperlattice Composition Spreads, K.-S. Chang, M. Aronova, C. Gao, C. Lin, Jason Hattrick-Simpers, M. Murakami, I. Takeuchi
Exploration Of Magnetoelectric Thin-Film Sensors Using Supperlattice Composition Spreads, K.-S. Chang, M. Aronova, C. Gao, C. Lin, Jason Hattrick-Simpers, M. Murakami, I. Takeuchi
Jason R. Hattrick-Simpers
No abstract provided.
Giant Magnetostriction In Annealed Co1-XFeX Thin-Films, Dwight Hunter, Will Osborn, Ke Wang, Nataliya Kazantseva, Jason R. Hattrick-Simpers, Richard Suchoski, Ryota Takahashi, Marcus L. Young, Apurva Mehta, Leonid A. Bendersky, Same E. Lofland, Manfred Wuttig, Ichiro Takeuchi
Giant Magnetostriction In Annealed Co1-XFeX Thin-Films, Dwight Hunter, Will Osborn, Ke Wang, Nataliya Kazantseva, Jason R. Hattrick-Simpers, Richard Suchoski, Ryota Takahashi, Marcus L. Young, Apurva Mehta, Leonid A. Bendersky, Same E. Lofland, Manfred Wuttig, Ichiro Takeuchi
Jason R. Hattrick-Simpers
Chemical and structural heterogeneity and the resulting interaction of coexisting phases can lead to extraordinary behaviours in oxides, as observed in piezoelectric materials at morphotropic phase boundaries and relaxor ferroelectrics. However, such phenomena are rare in metallic alloys. Here we show that, by tuning the presence of structural heterogeneity in textured Co1−xFex thin films, effective magnetostriction λeff as large as 260 p.p.m. can be achieved at low-saturation field of ~10 mT. Assuming λ100 is the dominant component, this number translates to an upper limit of magnetostriction ofλ100≈5λeff >1,000 p.p.m. Microstructural analyses …
Characterization Of Magnetic Degradation Mechanism In A High Neutron-Flux Environment, Adib Samin, Jie Qiu, Jason Hattrick-Simpers, Liyang Dai-Hattrick, Yuan Zheng, Lei Cao
Characterization Of Magnetic Degradation Mechanism In A High Neutron-Flux Environment, Adib Samin, Jie Qiu, Jason Hattrick-Simpers, Liyang Dai-Hattrick, Yuan Zheng, Lei Cao
Jason R. Hattrick-Simpers
No abstract provided.
Combinatorial Study Of Thin Film Metal Hydride By Prompt Gamma Activation Analysis, L. Cao, Jason Hattrick-Simpers, R. Bindel, R. Bindel, B. Tomlin, R. Zeisler, R. Paul, L. Bendersky, R. Downing
Combinatorial Study Of Thin Film Metal Hydride By Prompt Gamma Activation Analysis, L. Cao, Jason Hattrick-Simpers, R. Bindel, R. Bindel, B. Tomlin, R. Zeisler, R. Paul, L. Bendersky, R. Downing
Jason R. Hattrick-Simpers
No abstract provided.
Combinatorial Search Of Thermoelastic Shape-Memory Alloys With Extremely Small Hysteresis Width, Jun Cui, Yong Chu, Olugbenga Famodu, Yasubumi Furuya, Jason Hattrick-Simpers, Richard James, Alfred Ludwig, Sigurd Thienhaus, Manfred Wuttig, Zhiyong Zhang, Ichiro Takeuchi
Combinatorial Search Of Thermoelastic Shape-Memory Alloys With Extremely Small Hysteresis Width, Jun Cui, Yong Chu, Olugbenga Famodu, Yasubumi Furuya, Jason Hattrick-Simpers, Richard James, Alfred Ludwig, Sigurd Thienhaus, Manfred Wuttig, Zhiyong Zhang, Ichiro Takeuchi
Jason R. Hattrick-Simpers
No abstract provided.
Tunable Multiferroic Properties In Nanocomposite Pbtio3-Cofe2O4 Epitaxial Thin Films, M. Murakami, K.-S. Chang, M. Aronova, C.-L. Lin, Ming Yu, Jason Hattrick-Simpers, M. Wuttig, I. Takeuchi, C. Gao, B. Hu, S. Lofland, L. Knauss, L. Bendersky
Tunable Multiferroic Properties In Nanocomposite Pbtio3-Cofe2O4 Epitaxial Thin Films, M. Murakami, K.-S. Chang, M. Aronova, C.-L. Lin, Ming Yu, Jason Hattrick-Simpers, M. Wuttig, I. Takeuchi, C. Gao, B. Hu, S. Lofland, L. Knauss, L. Bendersky
Jason R. Hattrick-Simpers
We report on the synthesis of PbTiO3–CoFe2O4 multiferroic nanocomposites and continuous tuning of their ferroelectric and magnetic properties as a function of the average composition on thin-film composition spreads. The highest dielectric constant and nonlinear dielectric signal was observed at (PbTiO3)85–(CoFe2O4)15, where robust magnetism was also observed. Transmission electron microscopy revealed a pancake-shaped epitaxial nanostructure of PbTiO3 on the order of 30 nm embedded in the matrix of CoFe2O4 at this composition. Composition dependent ferroics properties observed here indicate that there is considerable interdiffusion of cations into each other.
Effects Of Neutron And Gamma Radiation On Lithium-Ion Batteries, Jie Qiu, Dandan He, Mingzhai Sun, Shimeng Li, Cun Wen, Jason Hattrick-Simpers, Yuan Zheng, Lei Cao
Effects Of Neutron And Gamma Radiation On Lithium-Ion Batteries, Jie Qiu, Dandan He, Mingzhai Sun, Shimeng Li, Cun Wen, Jason Hattrick-Simpers, Yuan Zheng, Lei Cao
Jason R. Hattrick-Simpers
No abstract provided.
Exploration Of Artificial Multiferroic Thin-Film Heterostructures Using Composition Spreads, K.-S. Chang, M. A. Aronova, C.-L. Lin, M. Murakami, M.-H. Yu, Jason R. Hattrick-Simpers, O. O. Famodu, S. Y. Lee, R. Ramesh, M. Wuttig, I. Takeuchi, C. Gao, L. A. Bendersky
Exploration Of Artificial Multiferroic Thin-Film Heterostructures Using Composition Spreads, K.-S. Chang, M. A. Aronova, C.-L. Lin, M. Murakami, M.-H. Yu, Jason R. Hattrick-Simpers, O. O. Famodu, S. Y. Lee, R. Ramesh, M. Wuttig, I. Takeuchi, C. Gao, L. A. Bendersky
Jason R. Hattrick-Simpers
We have fabricated a series of composition spreads consisting of ferroelectric BaTiO3 and piezomagnetic CoFe2O4 layers of varying thicknesses modulated at nanometer level in order to explore artificial magnetoelectricthin-film heterostructures. Scanning microwavemicroscopy and scanning superconducting quantum interference device microscopy were used to map the dielectric and magnetic properties as a function of continuously changing average composition across the spreads, respectively. Compositions in the middle of the spreads were found to exhibit ferromagnetism while displaying a dielectric constant as high as ≈120.
Multimode Quantitative Scanning Microwave Microscopy Of In Situ Grown Epitaxial Ba1-XSrXTio3 Composition Spreads, K. Chang, M. Aronova, O. Famodu, I. Takeuchi, S. Lofland, Jason Hattrick-Simpers, H. Chang
Multimode Quantitative Scanning Microwave Microscopy Of In Situ Grown Epitaxial Ba1-XSrXTio3 Composition Spreads, K. Chang, M. Aronova, O. Famodu, I. Takeuchi, S. Lofland, Jason Hattrick-Simpers, H. Chang
Jason R. Hattrick-Simpers
We have performed variable-temperature multimode quantitative microwavemicroscopy of in situepitaxial Ba1−xSrxTiO3 thin-film composition spreads fabricated on (100) LaA1O3 substrates. Dielectric properties were mapped as a function of continuously varying composition from BaTiO3 to SrTiO3. We have demonstrated nondestructive temperature-dependent dielectric characterization of local thin-film regions. Measurements are simultaneously taken at multiple resonant frequencies of the microscope cavity. The multimode measurements allow frequency dispersion studies. We observe strong composition-dependent dielectric relaxation in Ba1−xSrxTiO3 at microwave frequencies.