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Full-Text Articles in Engineering
Strain-Induced Magnetic Phase Transition In Srcoo3−Δ Thin Films, S J. Callori, S Hu, Joel Bertinshaw, Zhilian Yue, S Danilkin, Xiaolin Wang, V Nagarajan, Frank Klose, Jan Seidel, Clemens Ulrich
Strain-Induced Magnetic Phase Transition In Srcoo3−Δ Thin Films, S J. Callori, S Hu, Joel Bertinshaw, Zhilian Yue, S Danilkin, Xiaolin Wang, V Nagarajan, Frank Klose, Jan Seidel, Clemens Ulrich
Australian Institute for Innovative Materials - Papers
It has been well established that both in bulk at ambient pressure and for films under modest strains, cubic SrCoO3−δ (δ<0.2) is a ferromagnetic metal. Recent theoretical work, however, indicates that a magnetic phase transition to an antiferromagnetic structure could occur under large strain accompanied by a metal-insulator transition. We have observed a strain-induced ferromagnetic-to-antiferromagnetic phase transition in SrCoO3−δ films grown on DyScO3 substrates, which provide a large tensile epitaxial strain, as compared to ferromagnetic films under lower tensile strain on SrTiO3 substrates. Magnetometry results demonstrate the existence of antiferromagnetic spin correlations and neutron diffraction experiments provide a direct evidence for a G-type antiferromagnetic structure with Neél temperatures between TN∼135±10K and ∼325±10K, depending on the oxygen content of the samples. Therefore, our data experimentally confirm the predicted strain-induced magnetic phase transition to an antiferromagnetic state for SrCoO3−δ thin films under large epitaxial strain.
Ferroelectric And Magnetic Properties Of Aurivillius Bim+1ti3fem−3o3m+3 Thin Films, Tingting Jia, Hideo Kimura, Zhenxiang Cheng, Hongyang Zhao
Ferroelectric And Magnetic Properties Of Aurivillius Bim+1ti3fem−3o3m+3 Thin Films, Tingting Jia, Hideo Kimura, Zhenxiang Cheng, Hongyang Zhao
Australian Institute for Innovative Materials - Papers
Aurivillius Bim+1Ti3Fem−3O3m+3 (m = 4, 5, 6) thin films have been deposited by a pulsed laser deposition system. The x-ray diffraction patterns indicate the formation of orthorhombic phase. The remanent polarization (2Pr) of Bim+1Ti3Fem−3O3m+3 thin films is decreased with the m-number. Positive-up-negative-down measurements indicate the presence of ferroelectric (FE) polarization in as-obtained thin films. Piezoresponse force microscopy investigations confirm the existence of FE domains and the switchable polarization. Weak magnetic moment is detected in the Aurivillius films at room temperature. The present work …
Ultrafast Spin Polarization In A Multiferroic Manganite Bife0.5mn0.5o3 Thin Film, Zeyu Zhang, Zuanming Jin, Xian Lin, Zhenxiang Cheng, H Y. Zhao, Hideo Kimura, Guohong Ma
Ultrafast Spin Polarization In A Multiferroic Manganite Bife0.5mn0.5o3 Thin Film, Zeyu Zhang, Zuanming Jin, Xian Lin, Zhenxiang Cheng, H Y. Zhao, Hideo Kimura, Guohong Ma
Australian Institute for Innovative Materials - Papers
In this work, we present observations of ultrafast carrier dynamics and spin polarization in a multiferroic manganite BiFe0.5Mn0.5O3 film excited by linearly and circularly polarized femtosecond pulses, respectively. The d-band charge transfer transition is reasonably assigned to Γ3 → Γ5. The transient reflectivity decay on a time scale as fast as only 0.3 ps is consistent with the picture of ultrafast electron-phonon coupling. The ultrafast switching of polarization ellipticity (< 150 fs) originates from a transient coherent spin polarization by optical orientation. The ultrafast spin polarization switching is assigned to the Raman coherence process.
In Situ Anchoring Uniform Mno2 Nanosheets On Three-Dimensional Macroporous Graphene Thin-Films For Supercapacitor Electrodes, Yong Zhao, Yuena Meng, Haiping Wu, Yue Wang, Zhixiang Wei, Xiaojun Li, Peng Jiang
In Situ Anchoring Uniform Mno2 Nanosheets On Three-Dimensional Macroporous Graphene Thin-Films For Supercapacitor Electrodes, Yong Zhao, Yuena Meng, Haiping Wu, Yue Wang, Zhixiang Wei, Xiaojun Li, Peng Jiang
Australian Institute for Innovative Materials - Papers
We present a facile and efficient fabrication of 3D macroporous rGO/MnO2 nanosheet thin-films for supercapacitor electrodes. An amorphous-carbon-modified rGO thin-film is firstly prepared through a simple glucose and CaCO3 particle mediated template method. Then ultrathin MnO2 nanosheets are in situ synthesized on the rGO networks by the rapid and scalable redox reaction between KMnO4 and amorphous carbon. The fabricated three-dimensional porous hybrid thin-film shows a high specific capacitance of 245 F g-1 (based on the total mass of the film) at a scan rate of 2 mV s-1, a good rate capability of 143 F g-1 at 300 mV s-1, …
Increased Upconversion Performance For Thin Film Solar Cells: A Trimolecular Composition, Yuen Yap Cheng, Andrew Nattestad, Tim F. Schulze, Rowan W. Macqueen, Burkhard Fückel, Klaus Lips, Gordon G. Wallace, Tony Khoury, Maxwell J. Crossley, Timothy W. Schmidt
Increased Upconversion Performance For Thin Film Solar Cells: A Trimolecular Composition, Yuen Yap Cheng, Andrew Nattestad, Tim F. Schulze, Rowan W. Macqueen, Burkhard Fückel, Klaus Lips, Gordon G. Wallace, Tony Khoury, Maxwell J. Crossley, Timothy W. Schmidt
Australian Institute for Innovative Materials - Papers
Photochemical upconversion based on triplet-triplet annihilation (TTA-UC) is employed to enhance the short-circuit currents generated by two varieties of thin-film solar cells, a hydrogenated amorphous silicon (a-Si:H) solar cell and a dye-sensitized solar cell (DSC). TTA-UC is exploited to harvest transmitted sub-bandgap photons, combine their energies and re-radiate upconverted photons back towards the solar cells. In the present study we employ a dual-emitter TTA-UC system which allows for significantly improved UC quantum yields as compared to the previously used single-emitter TTA systems. In doing so we achieve record photo-current enhancement values for both the a-Si:H device and the DSC, surpassing …
Protein Nanorings Organized By Poly(Styrene-Block-Ethylene Oxide) Self-Assembled Thin Films, Jenny Malmström, Akshita Wason, Fergus Roache, N. Amy Yewdall, Mazdak Radjainia, Shanghai Wei, Michael J. Higgins, David Williams, Juliet A. Gerrard, Jadranka Travas-Sejdic
Protein Nanorings Organized By Poly(Styrene-Block-Ethylene Oxide) Self-Assembled Thin Films, Jenny Malmström, Akshita Wason, Fergus Roache, N. Amy Yewdall, Mazdak Radjainia, Shanghai Wei, Michael J. Higgins, David Williams, Juliet A. Gerrard, Jadranka Travas-Sejdic
Australian Institute for Innovative Materials - Papers
This study explores the use of block copolymer self-assembly to organize Lsmα, a protein which forms stable doughnut-shaped heptameric structures. Here, we have explored the idea that 2-D crystalline arrays of protein filaments can be prepared by stacking doughnut shaped Lsmα protein into the poly(ethylene oxide) blocks of a hexagonal microphase-separated polystyrene-b-polyethylene oxide (PS-b-PEO) block copolymer. We were able to demonstrate the coordinated assembly of such a complex hierarchical nanostructure. The key to success was the choice of solvent systems and protein functionalization that achieved sufficient compatibility whilst still promoting assembly. Unambiguous characterisation of these structures is difficult; however AFM …
An Investigation Of The Nanomechanical Properties Of 0.5ba(Ti0.8zr0.2)O3-0.5(Ba0.7ca0.3)Tio3 Thin Films, Zhong-Lan Cai, Zeng-Mei Wang, Huan-Huan Wang, Zhenxiang Cheng, Baowen Li, Xin-Li Guo, Hideo Kimura, Akira Kasahara
An Investigation Of The Nanomechanical Properties Of 0.5ba(Ti0.8zr0.2)O3-0.5(Ba0.7ca0.3)Tio3 Thin Films, Zhong-Lan Cai, Zeng-Mei Wang, Huan-Huan Wang, Zhenxiang Cheng, Baowen Li, Xin-Li Guo, Hideo Kimura, Akira Kasahara
Australian Institute for Innovative Materials - Papers
For practical application, the functional piezoelectric film in microelectromechanical systems should meet the requirement of physical properties, as well as the mechanical properties. In this article, 0.5Ba(Ti0.8Zr0.2)O3-0.5(Ba0.7Ca0.3)TiO3 (0.5BZT-0.5BCT) thin films with varied properties were prepared on (100) Si substrates via a sol-gel technique at different annealing temperatures. The effects of the annealing temperature on the morphology, piezoelectricity, hardness, and elastic modulus were studied. Particular attention was paid to the surface frictional behavior of films, and the changes in the friction force can be radically explained in terms of differences in the hardness/elastic modulus ratio and the residual stress of films. …
Analysis Of Low-Field Isotropic Vortex Glass Containing Vortex Groups In Yba2cu3o7−X Thin Films Visualized By Scanning Squid Microscopy, Frederick Wells, Alexey V. Pan, Renshaw Wang, Sergey Fedoseev, Hans Hilgenkamp
Analysis Of Low-Field Isotropic Vortex Glass Containing Vortex Groups In Yba2cu3o7−X Thin Films Visualized By Scanning Squid Microscopy, Frederick Wells, Alexey V. Pan, Renshaw Wang, Sergey Fedoseev, Hans Hilgenkamp
Australian Institute for Innovative Materials - Papers
The glass-like vortex distribution in pulsed laser deposited YBa2Cu3O7 − x thin films is observed by scanning superconducting quantum interference device microscopy and analysed for ordering after cooling in magnetic fields significantly smaller than the Earth's field. Autocorrelation calculations on this distribution show a weak short-range positional order, while Delaunay triangulation shows a near-complete lack of orientational order. The distribution of these vortices is finally characterised as an isotropic vortex glass. Abnormally closely spaced groups of vortices, which are statistically unlikely to occur, are observed above a threshold magnetic field. The origin of these groups …
Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou
Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou
Australian Institute for Innovative Materials - Papers
We present a detailed investigation on the doping dependence of the upper critical fieldHc2(T) of FeSexTe1−xthin films (0.18 ≤ x ≤ 0.90) by measuring the electrical resistivity as a function of magnetic field. The Hc2(T) curves exhibit a downturn behavior with decreasing temperature in all the samples, owing to the Pauli-limited effect (spin paramagnetic effect). The Pauli-limited effect on the upper critical field can be monotonically modulated by variation of the Se/Te composition. Our results show that Te-doping induced disorder and excess Fe atoms give rise to enhancement of the Pauli-limited effect.