@article{kotsonis_rost_harris_maria_2018, title={Epitaxial entropy-stabilized oxides: growth of chemically diverse phases via kinetic bombardment}, volume={8}, ISSN={["2159-6867"]}, DOI={10.1557/mrc.2018.184}, abstractNote={This paper explores thin films of the entropy-stabilized oxide (ESO) composition Mg_xNi_xCo_xCuxZn_xSc_xO (x~ 0.167) grown by laser ablation in incremental gas pressures and O_2/Ar ratios to modulate particle kinetic energy and plume reactivity. Low pressures supporting high kinetic energy adatoms favor the kinetic stabilization of a single rocksalt phase, while high pressures (low kinetic energy adatoms) result in phase separation. The pressure threshold for phase separation is a function of O_2/Ar ratio. These findings suggest large kinetic energies facilitate the assembly and quench of metastable ESO phases that may require immoderate physical or chemical conditions to synthesize using near-equilibrium techniques.}, number={3}, journal={MRS COMMUNICATIONS}, author={Kotsonis, George N. and Rost, Christina M. and Harris, David T. and Maria, Jon-Paul}, year={2018}, month={Sep}, pages={1371–1377} }
 @article{harris_burch_mily_dickey_maria_2016, title={Microstructure and dielectric properties with CuO additions to liquid phase sintered BaTiO3 thin films}, volume={31}, ISSN={0884-2914 2044-5326}, url={http://dx.doi.org/10.1557/jmr.2016.89}, DOI={10.1557/jmr.2016.89}, abstractNote={Abstract}, number={8}, journal={Journal of Materials Research}, publisher={Cambridge University Press (CUP)}, author={Harris, David T. and Burch, Matthew J. and Mily, Edward J. and Dickey, Elizabeth C. and Maria, Jon-Paul}, year={2016}, month={Mar}, pages={1018–1026} }
 @article{ihlefeld_harris_keech_jones_maria_trolier-mckinstry_2016, title={Scaling Effects in Perovskite Ferroelectrics: Fundamental Limits and Process-Structure-Property Relations}, volume={99}, ISSN={["1551-2916"]}, DOI={10.1111/jace.14387}, abstractNote={Ferroelectric materials are well‐suited for a variety of applications because they can offer a combination of high performance and scaled integration. Examples of note include piezoelectrics to transform between electrical and mechanical energies, capacitors used to store charge, electro‐optic devices, and nonvolatile memory storage. Accordingly, they are widely used as sensors, actuators, energy storage, and memory components, ultrasonic devices, and in consumer electronics products. Because these functional properties arise from a noncentrosymmetric crystal structure with spontaneous strain and a permanent electric dipole, the properties depend upon physical and electrical boundary conditions, and consequently, physical dimension. The change in properties with decreasing physical dimension is commonly referred to as a size effect. In thin films, size effects are widely observed, whereas in bulk ceramics, changes in properties from the values of large‐grained specimens is most notable in samples with grain sizes below several micrometers. It is important to note that ferroelectricity typically persists to length scales of about 10 nm, but below this point is often absent. Despite the stability of ferroelectricity for dimensions greater than ~10 nm, the dielectric and piezoelectric coefficients of scaled ferroelectrics are suppressed relative to their bulk counterparts, in some cases by changes up to 80%. The loss of extrinsic contributions (domain and phase boundary motion) to the electromechanical response accounts for much of this suppression. In this article, the current understanding of the underlying mechanisms for this behavior in perovskite ferroelectrics is reviewed. We focus on the intrinsic limits of ferroelectric response, the roles of electrical and mechanical boundary conditions, grain size and thickness effects, and extraneous effects related to processing. In many cases, multiple mechanisms combine to produce the observed scaling effects.}, number={8}, journal={JOURNAL OF THE AMERICAN CERAMIC SOCIETY}, author={Ihlefeld, Jon F. and Harris, David T. and Keech, Ryan and Jones, Jacob L. and Maria, Jon-Paul and Trolier-McKinstry, Susan}, year={2016}, month={Aug}, pages={2537–2557} }
 @article{harris_burch_li_dickey_maria_2015, title={Low‐Temperature Control of Twins and Abnormal Grain Growth in BaTiO
            3}, volume={98}, ISSN={0002-7820 1551-2916}, url={http://dx.doi.org/10.1111/jace.13643}, DOI={10.1111/jace.13643}, abstractNote={The microstructure of polycrystalline barium titanate (BaTiO3) thin films processed with a liquid‐phase can be controlled by the crystallographic orientation of the underlying sapphire substrate. During postdeposition crystallization, the tendency for {111} twin nucleation, which drives subsequent abnormal grain growth, depends upon the specific sapphire facet. Specifically, tilting away from the close‐packed c‐plane modifies the orientation, morphology, and relative amount of an interfacial BaAl2O4 second phase. These factors control the density of twin formation, and thus overall grain size of the crystallized BaTiO3. As the substrate orientation transitions from c‐plane, to r‐plane, to a‐plane, the twin density is reduced, the average grain size decreases systematically from 270 to 130 nm, and the grain structure becomes overall more homogeneous. This twinning mechanism and abnormal grain growth occur by 900°C, several hundred degrees lower than reported previously.}, number={8}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Harris, David T. and Burch, Matthew J. and Li, Jing and Dickey, Elizabeth C. and Maria, Jon‐Paul}, editor={Viehland, D.Editor}, year={2015}, month={May}, pages={2381–2387} }
 @article{burch_li_harris_maria_dickey_2014, title={Mechanisms for microstructure enhancement in flux-assisted growth of barium titanate on sapphire}, volume={29}, ISSN={0884-2914 2044-5326}, url={http://dx.doi.org/10.1557/jmr.2014.59}, DOI={10.1557/jmr.2014.59}, abstractNote={Abstract}, number={7}, journal={Journal of Materials Research}, publisher={Cambridge University Press (CUP)}, author={Burch, Matthew J. and Li, Jing and Harris, David T. and Maria, Jon-Paul and Dickey, Elizabeth C.}, year={2014}, month={Mar}, pages={843–848} }
 @article{garten_lam_harris_maria_trolier-mckinstry_2014, title={Residual ferroelectricity in barium strontium titanate thin film tunable dielectrics}, volume={116}, DOI={10.1063/1.4891717}, abstractNote={Loss reduction is critical to develop Ba1−xSrxTiO3 thin film tunable microwave dielectric components and dielectric energy storage devices. The presence of ferroelectricity, and hence the domain wall contributions to dielectric loss, will degrade the tunable performance in the microwave region. In this work, residual ferroelectricity—a persistent ferroelectric response above the global phase transition temperature—was characterized in tunable dielectrics using Rayleigh analysis. Chemical solution deposited Ba0.7Sr0.3TiO3 films, with relative tunabilities of 86% over 250 kV/cm at 100 kHz, demonstrated residual ferroelectricity 65 °C above the ostensible paraelectric transition temperature. Frequency dispersion observed in the dielectric temperature response was consistent with the presence of nanopolar regions as one source of residual ferroelectricity. The application of AC electric field for the Rayleigh analysis of these samples led to a doubling of the dielectric loss for fields over 10 kV/cm at room temperature.}, number={4}, journal={Journal of Applied Physics}, author={Garten, L. M. and Lam, P. and Harris, D. and Maria, J. P. and Trolier-McKinstry, S.}, year={2014} }
 @article{harris_lam_burch_li_rogers_dickey_maria_2014, title={Ultra-high tunability in polycrystalline Ba1−xSrxTiO3 thin films}, volume={105}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.4893615}, DOI={10.1063/1.4893615}, abstractNote={Ba0.7Sr0.3TiO3 thin polycrystalline films with an ultra-high capacitance tunability approaching 5:1 at 175 kV/cm were made possible by a flux-assisted synthesis approach. In this process, a small volume fraction of a low melting temperature glass is added during low-temperature sputter deposition. Subsequent annealing activates the liquid phase, which in turn provides the mass transport needed to approach full density, to increase grain size, and to improve crystallinity, and, in so doing, achieves a stronger non-linear dielectric response. Ba0.7Sr0.3TiO3 films with 0%, 1%, 4%, and 7% BaO-3B2O3 flux exhibited grain sizes of 25 nm, 28 nm, 48 nm, and 56 nm, and dielectric tunabilities of 25%, 33%, 64%, and 80% respectively. These values represent substantial improvements when compared to conventionally processed tunable dielectric films.}, number={7}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Harris, D. T. and Lam, P. G. and Burch, M. J. and Li, J. and Rogers, B. J. and Dickey, E. C. and Maria, J.-P.}, year={2014}, month={Aug}, pages={072904} }
 @article{harris_burch_ihlefeld_lam_li_dickey_maria_2013, title={Realizing strain enhanced dielectric properties in BaTiO3 films by liquid phase assisted growth}, volume={103}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.4813270}, DOI={10.1063/1.4813270}, abstractNote={The addition of a liquid-forming flux to barium titanate thin films promotes densification and grain growth, improves nonlinear dielectric properties, and allows residual strain to be sustained in polycrystalline films without cracking at thicknesses relevant to device fabrication. Relative tuning, an excellent indicator of crystalline quality and an important material property for tunable microwave devices, increases from 20% to 70%. Films exhibit 0.15% residual differential thermal expansion mismatch strain, resulting in a shift to the paraelectric-ferroelectric phase transition of 50 °C. This result is in excellent agreement with theory, demonstrating the ability to tune ferroic transitions without epitaxial approaches.}, number={1}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Harris, David T. and Burch, Matthew J. and Ihlefeld, Jon F. and Lam, Peter G. and Li, Jing and Dickey, Elizabeth C. and Maria, Jon-Paul}, year={2013}, month={Jul}, pages={012904} }
 @article{burch_harris_white_moballegh_li_maria_dickey_2012, title={In situ heating studies of flux grown barium titanate thin films}, volume={18}, url={https://app.dimensions.ai/details/publication/pub.1054927598}, DOI={10.1017/s1431927612009245}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.}, number={S2}, journal={Microscopy and Microanalysis}, author={Burch, M.J. and Harris, D. and White, R.M. and Moballegh, A. and Li, J. and Maria, J.P. and Dickey, Elizabeth C.}, year={2012}, pages={1478–1479} }