Dielectric anomaly and magnetic response of epitaxial orthorhombic YMnO3 thin films

The structure, magnetic response, and dielectric response of the grown epitaxial thin films of the orthorhombic phase of YMnO3 oxide on Nb:SrTiO3 (001) substrates have been measured. We have found that a substrate-induced strain produces an in-plane compression of the YMnO3 unit cell. The magnetization versus temperature curves display a significant zero-field cooling (ZFC)-field cooling hysteresis below the Néel temperature (TN ≈ 45 K). The dielectric constant increases gradually (up to 26%) below the TN and mimics the ZFC magnetization curve. We argue that these effects could be a manifestation of magnetoelectric coupling in YMnO3 thin films and that the magnetic structure of YMnO3 can be controlled by substrate selection and/or growth conditions.

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Atomic Layer Growth of High Tc (Ca,Sr)CuO2 Thin Films by Laser Mbe

MRS Proceedings ◽

10.1557/proc-285-257 ◽

1992 ◽

Vol 285 ◽

Author(s):

M. Kana ◽

T. Kawai ◽

S. Kawai

Keyword(s):

Thin Films ◽

High Temperature Superconductivity ◽

Atomic Layer ◽

Layer Growth ◽

Zero Field ◽

High Tc ◽

Layer Stacking ◽

Laser Mbe ◽

Zero Field Cooling ◽

Field Cooling

ABSTRACTResistive and magnetic anomalies were observed at 150-170K in Ca0.3Sr0.7CuO2 thin films prepared by atomic-layer stacking using laser molecular beam epitaxy. Systematic current density dependence of the resistivity was observed below these temperatures with clear resistivity drops. At the same temperature range, the films showed diamagnetic response and hysteresis of magnetization between zero-field cooling and field cooling process. These behaviors suggest that the anomalies are due to high temperature superconductivity around 150-170K in the Ca0.3Sr0.7CuO2 thin films.

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Characterization of Epitaxial Superconducting YBacuO Thin Films with Three Different Orientations

MRS Proceedings ◽

10.1557/proc-169-679 ◽

1989 ◽

Vol 169 ◽

Author(s):

X.K. Wang ◽

D.X. Li ◽

S.N. Song ◽

J.Q. Zheng ◽

R.P.H. Chang ◽

...

Keyword(s):

Thin Films ◽

Critical Current Density ◽

Critical Current ◽

Current Density ◽

Orientation Dependence ◽

Zero Field ◽

Epitaxial Thin Films ◽

Oriented Film ◽

Zero Resistance ◽

Xrd Patterns

AbstractEpitaxial thin films of YBaCuO were prepared by multilayer deposition from Y, Cu, and BaF2 sources with: (1) the a‐axis perpendicular to (100)SrTiO3; (2) the c‐axis perpendicular to (100)SrTiO3; and (3) the [110] axis perpendicular to (110)SrTiO3. XRD patterns as well as SEM and HREM images confirm that the films are highly oriented, essentially epitaxial. Both the a‐axis oriented and the c‐axis oriented films exhibit zero resistance at 91K. The [110] oriented film shows the sharpest transiton with a transition width of IK and zero resistance at 85K. The zero field critical current density, Jc, determined magnetically, is in excess of 107A/cm2 at 4.4K and 1.04 x 106A/cm2 at 77K for the c‐axis oriented film; for the a‐axis oriented film we obtained 6.7 x 106A/cm2 at 4.4K and 1.2 x 105A/cm2 at 77K. The orientation dependence of the critical current density in the basal plane of the a‐axis oriented film was studied. The largest Jc's occur along the in‐plane <100> axes of the substrate.

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Effects of Parameters of High-Temperature Superconductor Levitation System on the Vertical Force in Zero-Field Cooling when a Permanent Magnet Is Laterally Traversing

Journal of Superconductivity and Novel Magnetism ◽

10.1007/s10948-008-0406-0 ◽

2008 ◽

Vol 22 (4) ◽

pp. 381-385 ◽

Cited By ~ 2

Author(s):

Yong Yang

Keyword(s):

High Temperature ◽

Permanent Magnet ◽

High Temperature Superconductor ◽

Zero Field ◽

Vertical Force ◽

Levitation System ◽

Zero Field Cooling ◽

Field Cooling

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Síntesis del superconductor YBa2Cu3O7- δ mediante sinterización por descarga luminiscente anormal

Revista de la Academia Colombiana de Ciencias Exactas Físicas y Naturales ◽

10.18257/raccefyn.428 ◽

2017 ◽

Vol 41 (158) ◽

pp. 36

Author(s):

Erika Yazmin Soto-Gómez ◽

Armando Sarmiento-Santos ◽

Carlos Arturo Parra-Vargas

Keyword(s):

Zero Field ◽

Zero Field Cooling ◽

Field Cooling

En este trabajo se reporta la síntesis del superconductor YBa2Cu3O7-δ mediante el método no convencional de sinterización por plasma en el rango de descarga luminiscente anormal (DLA). Las muestras se sometieron a diferentes temperaturas y tiempos de sinterización. Como referencia se usó una muestra superconductora obtenida por el método convencional (horno resistivo). La caracterización estructural de estas muestras se hizo por difracción de rayos X y refinamiento con el método de Rietveld. El comportamiento superconductor se determinó mediante el análisis de las curvas de magnetización en función de la temperatura según los procedimientos experimentales de enfriado en campo magnético cero (zero field cooling, ZFC) y enfriado con campo magnético aplicado (field cooling, FC). Las muestras sinterizadas por DLA presentaron características estructurales (ortorrómbica Pmmm) y superconductoras con una temperatura crítica de Tc~ 92 K, similares a las obtenidas por el método convencional, pero con una significativa reducción en las temperaturas y tiempos, bajo un ambiente adecuado de presión en el proceso de sinterización. © 2017. Acad. Colomb. Cienc. Ex. Fis. Nat.

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Crystallization of Epitaxial Lanthanum Aluminate and Spinel Thin Films Derived from Nitrate Precursors

MRS Proceedings ◽

10.1557/proc-341-145 ◽

1994 ◽

Vol 341 ◽

Cited By ~ 2

Author(s):

Man Fai Ng ◽

Michael J. Cima

Keyword(s):

Thin Films ◽

Epitaxial Film ◽

Amorphous Film ◽

Zero Field ◽

Epitaxial Thin Films ◽

Lanthanum Aluminate ◽

Initial Nucleation ◽

Metalorganic Deposition ◽

Current Densities ◽

Higher Temperature

AbstractBoth lanthanum aluminate (LaAIO 3) and spinel (MgAl2O 4) epitaxial thin films have been deposited on either planar and stepped (100) SrTiO3 single crystal substrates by pyrolysis of mixed nitrate precursors. The precursors pyrolyze initially into amorphous films. Nucleation of lanthanum aluminate and spinel occurs at the filnVsubstrate interface at higher temperature. Crystallization of LaAlO3 on SrTiO3 substrates occurs at approximately 650°C, whereas nucleation occurs at approximately 800'C without lattice-matched substrates. Similarly, latticematched substrates reduce the crystallization temperature of spinel to below 700°C. The epitaxial film grows at the expense of the amorphous film after the initial nucleation at the interface. The rapid growth and volume change due to the crystallization leave behind an epitaxial film with nanoporosity of 15 to 30 nm. Nevertheless, the surfaces of these films have roughness of only 6–9 Å. Ba2Ycu3O7-x films derived from metalorganic deposition of metal trifluoroacetate precursors was deposited on these epitaxial LaAlO3 films on both planar and stepped SrTiO3 substrates. The resultant YBCO films on LaAlO3 film on planar SrTiO3 substrate have critical current densities of > 2 × 106 A/cm2 at 77K and zero field.

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Formation of the orthorhombic phase in CeO2-HfO2 solid solution epitaxial thin films and their ferroelectric properties

Applied Physics Letters ◽

10.1063/1.5097980 ◽

2019 ◽

Vol 114 (23) ◽

pp. 232902 ◽

Cited By ~ 2

Author(s):

T. Shiraishi ◽

S. Choi ◽

T. Kiguchi ◽

T. Shimizu ◽

H. Funakubo ◽

...

Keyword(s):

Thin Films ◽

Solid Solution ◽

Ferroelectric Properties ◽

Orthorhombic Phase ◽

Epitaxial Thin Films

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Iron-Doped Lithium Tantalate Thin Films Deposited by Magnetron Sputtering: A Study of the Iron Role in the Structure and the Derived Magnetic Properties

Crystals ◽

10.3390/cryst10010050 ◽

2020 ◽

Vol 10 (1) ◽

pp. 50 ◽

Cited By ~ 2

Author(s):

Sergio David Villalobos Mendoza ◽

José Trinidad Holguín Momaca ◽

José Trinidad Elizalde Galindo ◽

Diana María Carrillo Flores ◽

Sion Federico Olive Méndez ◽

...

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Magnetic Hysteresis ◽

Hysteresis Loops ◽

Blocking Temperature ◽

Ferromagnetic Behavior ◽

Zero Field ◽

Cooling Curves ◽

X Ray Diffraction ◽

Field Cooling

Fe-doped LiTaO3 thin films with a low and high Fe concentration (labeled as LTO:Fe-LC and LTO:Fe-HC, respectively) were deposited by magnetron sputtering from two home-made targets. The dopant directly influenced the crystalline structure of the LiTaO3 thin films, causing the contraction of the unit cell, which was related to the incorporation of Fe3+ ions into the LiTaO3 structure, which occupied Li positions. This substitution was corroborated by Raman spectroscopy, where the bands associated with Li-O bonds broadened in the spectra of the samples. Magnetic hysteresis loops, zero-field cooling curves, and field cooling curves were obtained in a vibrating sample magnetometer. The LTO:Fe-HC sample demonstrates superparamagnetic behavior with a blocking temperature of 100 K, mainly associated with the appearance of Fe clusters in the thin film. On the other hand, a room temperature ferromagnetic behavior was found in the LTO:Fe-LC layer where saturation magnetization (3.80 kAm−1) and magnetic coercivities were not temperature-dependent. Moreover, the crystallinity and morphology of the samples were evaluated by X-ray diffraction and scanning electron microscopy, respectively.

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