Author
Dave H. A. Blank
Other affiliations: University of Twente
Bio: Dave H. A. Blank is an academic researcher from MESA+ Institute for Nanotechnology. The author has contributed to research in topics: Thin film & Pulsed laser deposition. The author has an hindex of 33, co-authored 94 publications receiving 4264 citations. Previous affiliations of Dave H. A. Blank include University of Twente.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, the topmost oxide layer was observed to hydroxylate after immersion in water, which was used to enhance the etch-selectivity of SrO relative to TiO2 in a buffered HF solution.
Abstract: In recent years, well-defined and nearly perfect single crystal surfaces of oxide perovskites have become increasingly important. A single terminated surface is a prerequisite for reproducible thin film growth and fundamental growth studies. In this work, atomic and lateral force microscopy have been used to display different terminations of SrTiO3. We observe hydroxylation of the topmost SrO layer after immersion of SrTiO3 in water, which is used to enhance the etch-selectivity of SrO relative to TiO2 in a buffered HF solution. We reproducibly obtain perfect and single terminated surfaces, irrespective of the initial state of polished surfaces and the pH value of the HF solution. This approach to the problem might be used for a variety of multi-component oxide single crystals. True two-dimensional reflection high-energy electron diffraction intensity oscillations are observed during homo epitaxial growth using pulsed laser deposition on these surfaces.
693 citations
TL;DR: Based on transport, spectroscopic, and oxygen-annealing experiments, it is concluded that extrinsic defects in the form of oxygen vacancies introduced by the pulsed laser deposition process used by all researchers to date to make these samples is the source of the large carrier densities.
Abstract: As discovered by Ohtomo and Hwang, a large sheet charge density with high mobility exists at the interface between SrTiO3 and LaAlO3. Based on transport, spectroscopic, and oxygen-annealing experiments, we conclude that extrinsic defects in the form of oxygen vacancies introduced by the pulsed laser deposition process used by all researchers to date to make these samples is the source of the large carrier densities. Annealing experiments show a limiting carrier density. We also present a model that explains the high mobility based on carrier redistribution due to an increased dielectric constant.
492 citations
TL;DR: In this article, high temperature X-ray diffraction (HT-XRD), temperature programmed desorption (TPD), thermogravimetric analysis-differential thermal analysis (TGA/DTA) and neutron diffraction were combined to determine the structure and oxygen stoichiometry of SrCo0.8Fe0.2O3−δ (BSCF) up to 1273 K in the pO2 range of 1 to 10−5 atm.
187 citations
TL;DR: In this article, the authors observed a self-organized conversion of the terminating atomic layer from RuO2 to SrO. This conversion induces an abrupt change in growth mode from layer by layer to growth by step advancement, indicating a large enhancement of the surface diffusivity.
Abstract: During the initial growth of the ferromagnetic oxide SrRuO3 on TiO2-terminated SrTiO3, we observe a self-organized conversion of the terminating atomic layer from RuO2 to SrO. This conversion induces an abrupt change in growth mode from layer by layer to growth by step advancement, indicating a large enhancement of the surface diffusivity. This growth mode enables the growth of single-crystalline and single-domain thin films. Both conversion and the resulting growth mode enable the control of the interface properties in heteroepitaxial multilayer structures on an atomic level.
171 citations
TL;DR: In this article, the growth of spinel ZnMd62O4 M=Co, Rh, and Ir, a ρ-type wide band gap semiconductor by pulsed laser deposition, was reported.
Abstract: The authors report on the growth of spinel ZnMd62O4 M=Co, Rh, and Ir, a ρ-type wide band gap semiconductor by pulsed laser deposition. The band gap of these compounds is determined by the ligand field splitting in the subbands of the metallic d6 cation. Photoemission spectroscopy revealed that the valence band maximum is composed of occupied t2g 6 states. The observed band gap is increasing for higher quantum numbers, being as large as 3 eV for ZnIr2O4, which is expected from theoretical predictions. Grown in polycrystalline phase, films of these materials display high conductivity, well above 2 S cm−1.
143 citations
Cited by
More filters
Journal Article•
28,685 citations
TL;DR: This work reports on superconductivity in the electron gas formed at the interface between two insulating dielectric perovskite oxides, LaAlO3 and SrTiO3.
Abstract: At interfaces between complex oxides, electronic systems with unusual electronic properties can be generated. We report on superconductivity in the electron gas formed at the interface between two insulating dielectric perovskite oxides, LaAlO3 and SrTiO3. The behavior of the electron gas is that of a two-dimensional superconductor, confined to a thin sheet at the interface. The superconducting transition temperature of ≅ 200 millikelvin provides a strict upper limit to the thickness of the superconducting layer of ≅ 10 nanometers.
2,317 citations
TL;DR: Recent technical advances in the atomic-scale synthesis of oxide heterostructures have provided a fertile new ground for creating novel states at their interfaces, with characteristic feature is the reconstruction of the charge, spin and orbital states at interfaces on the nanometre scale.
Abstract: Recent technical advances in the atomic-scale synthesis of oxide heterostructures have provided a fertile new ground for creating novel states at their interfaces. Different symmetry constraints can be used to design structures exhibiting phenomena not found in the bulk constituents. A characteristic feature is the reconstruction of the charge, spin and orbital states at interfaces on the nanometre scale. Examples such as interface superconductivity, magneto-electric coupling, and the quantum Hall effect in oxide heterostructures are representative of the scientific and technological opportunities in this rapidly emerging field.
2,037 citations
TL;DR: Characterization and Properties 3928 8.2.1.
Abstract: 5. In Situ Polymerization 3907 5.1. General Polymerization 3907 5.2. Photopolymerization 3910 5.3. Surface-Initiated Polymerization 3912 5.4. Other Methods 3913 6. Colloidal Nanocomposites 3913 6.1. Sol-Gel Process 3914 6.2. In Situ Polymerization 3916 6.2.1. Emulsion Polymerization 3917 6.2.2. Emulsifier-Free Emulsion Polymerization 3919 6.2.3. Miniemulsion Polymerization 3920 6.2.4. Dispersion Polymerization 3921 6.2.5. Other Polymerization Methods 3923 6.2.6. Conducting Nanocomposites 3924 6.3. Self Assembly 3926 7. Other Preparative Methods 3926 8. Characterization and Properties 3928 8.1. Chemical Structure 3928 8.2. Microstructure and Morphology 3929 8.3. Mechanical Properties 3933 8.3.1. Tensile, Impact, and Flexural Properties 3933 8.3.2. Hardness 3936 8.3.3. Fracture Toughness 3937 8.3.4. Friction and Wear Properties 3937 8.4. Thermal Properties 3938 8.5. Flame-Retardant Properties 3941 8.6. Optical Properties 3942 8.7. Gas Transport Properties 3943 8.8. Rheological Properties 3945 8.9. Electrical Properties 3945 8.10. Other Characterization Techniques 3946 9. Applications 3947 9.1. Coatings 3947 9.2. Proton Exchange Membranes 3948 9.3. Pervaporation Membranes 3948 9.4. Encapsulation of Organic Light-Emitting Devices 3948
1,915 citations
TL;DR: In this paper, the surface of inorganic nanoparticles is modified to improve the interfacial interactions between the inorganic particles and the polymer matrix, which improves the properties of polymeric composites.
1,709 citations