El-Khatib, S., A. M. Alsmadi, V. Correa, A. V. Andreev, A. Lacerda, F. Nasreen, and H. Nakotte. "Electronic properties of single crystalline UNi[sub 0.39]Rh[sub 0.61]Al." Journal of Applied Physics 103, no. 7 (2008): 07B714–3.
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Sirena, M., A. Zimmers, N. Haberkorn, E. E. Kaul, L. B. Steren, J. Lesueur, T. Wolf, Y. Le Gall, J. - J. Grob, and G. Faini. "Direct observation of electronic inhomogeneities induced by point defect disorder in manganite films." Journal of Applied Physics 107 (2010): 113903.
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Ogando, K., and H. Pastoriza. "Design of integration-ready metasurface-based infrared absorbers." Journal of Applied Physics 118, no. 4 (2015): 043109.
Abstract: We introduce an integration ready design of metamaterial infrared absorber, highly compatible with many kinds of fabrication processes. We present the results of an exhaustive experimental characterization, including an analysis of the effects of single meta-atom geometrical parameters and collective arrangement. We confront the results with the theoretical interpretations proposed in the literature. Based on the results, we develop a set of practical design rules for metamaterial absorbers in the infrared region.
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Sirena, M., N. Haberkorn, M. Granada, L. B. Steren, and J. Guimpel. "Correlation between structure and magnetic properties of manganite-based multilayers." JOURNAL OF APPLIED PHYSICS 93, no. 10 (2003): 7244–7246.
Abstract: We have studied the structure, magnetic, and transport properties of manganite-based multilayers A/B-i, with A=La0.55Sr0.45MnO3 (metallic ferromagnet), and spacers (B-i) of different nature: B-1=SrTiO3 (nonmagnetic insulator), B-2=La0.9Sr0.1MnO3 (insulator ferromagnet), and B-3=La0.67Ca0.33MnO3 (paramagnetic-insulator/ferromagnet-metal). The samples are strongly textured in the direction perpendicular to the sample surface, and present a good interface quality with small roughness and interdiffusion. We have found that in the A/B-1/A trilayers, the ferromagnetic electrodes are ferromagnetically coupled for thin spacer layers and becomes decoupled for spacer thickness larger than 3 nm. Instead, the others multilayers are ferromagnetic for all spacer thicknesses and temperature range. This result was expected for temperatures well below the spacer Curie temperature. We attributed the ferromagnetic behavior of the system, found for temperatures above the ordering temperature of the spacer, to direct exchange coupling through short-range ordered zones in spacer layer. As expected from magnetization results, in fact, no extrinsic magnetoresistance was measured in these systems in the temperature range between 4.2 and 300 K. (C) 2003 American Institute of Physics.
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Navarro, H., I. Yang, M. Sirena, J. Kim, and N. Haberkorn. Characterization of the insulator barrier and the superconducting transition temperature in GdBa2Cu3O7−δ/BaTiO3 bilayers for application in tunnel junctions. Vol. 118., 2015.
Abstract: The optimization of the superconducting properties in a bottom electrode and the quality of an insulator barrier are the first steps in the development of superconductor/insulator/superconductor tunnel junctions. Here, we study the quality of a BaTiO3 tunnel barrier deposited on a 16 nm thick GdBa2Cu3O7−δ thin film by using conductive atomic force microscopy. We find that the tunnel current is systematically reduced (for equal applied voltage) by increasing the BaTiO3 barrier thickness between 1.6 and 4 nm. The BaTiO3 layers present an energy barrier of ≈1.2 eV and an attenuation length of 0.35–0.5 nm (depending on the applied voltage). The GdBa2Cu3O7−δ electrode is totally covered by a BaTiO3 thickness above 3 nm. The presence of ferroelectricity was verified by piezoresponse force microscopy for a 4 nm thick BaTiO3 top layer. The superconducting transition temperature of the bilayers is systematically suppressed by increasing the BaTiO3 thickness. This fact can be associated with stress at the interface and a reduction of the orthorhombicity of the GdBa2Cu3O7−δ. The reduction in the orthorhombicity is expected by considering the interface mismatch and it can also be affected by reduced oxygen stoichiometry (poor oxygen diffusion across the BaTiO3 barrier).
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