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Full-Text Articles in Physical Sciences and Mathematics
Investigation Of The Critical Behavior In Mn0.94nb 0.06coge Alloy By Using The Field Dependence Of Magnetic Entropy Change, J C. Debnath, P Shamba, A M. Strydom, Jianli Wang, S X. Dou
Investigation Of The Critical Behavior In Mn0.94nb 0.06coge Alloy By Using The Field Dependence Of Magnetic Entropy Change, J C. Debnath, P Shamba, A M. Strydom, Jianli Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
The critical behaviour of Mn0.94Nb0.06CoGe alloy around the paramagnetic-ferromagnetic phase transition was studied based on the field dependence on magnetic entropy change. By using the obtained exponents, the modified Arrott plot is consistent with that by using conventional method. These critical exponents are confirmed by the Widom scaling relation. Based on these critical exponents, the magnetization, field and temperature data around Tc collapse into two curves obeying the single scaling equation MðH; e)¼ebf6(H/ebþc). The calculated critical exponents not only obey the scaling theory but also anastomose the deduced results from the Kouvel-Fisher method [J. S. Kouvel and M. E. Fisher, …
Thermo-Magnetic Stability Of Superconducting Films Controlled By Nano-Morphology, V V. Yurchenko, K Ilin, J M. Meckbach, M Siegel, A J. Qviller, Y M. Galperin, Tom H. Johansen
Thermo-Magnetic Stability Of Superconducting Films Controlled By Nano-Morphology, V V. Yurchenko, K Ilin, J M. Meckbach, M Siegel, A J. Qviller, Y M. Galperin, Tom H. Johansen
Australian Institute for Innovative Materials - Papers
Appearance of dendritic magnetic flux avalanches in superconducting films, which are associated with thermo-magnetic instability (TMI), very often indicates serious limitations for the ultimate performance of superconducting devices made of type-II superconducting thin films. We demonstrate that the stability can be controlled by a thorough adjustment of samples morphology at nano-scale, which affects internal material parameters. By this, the metal coating, commonly used as for stabilization, becomes redundant. Most importantly, we directly show by the mean of magneto-optical imaging that introduction of nano-scaled disorder dramatically changes the mode of magnetic flux propagation in the superconductors, from uniform motion of individual …
Magnetism And Magnetic Structures Of Prmn2ge2-Xsix, Jianli Wang, S J. Campbell, M Hofmann, S J. Kennedy, R Zeng, M Md Din, S X. Dou, A Arulraj, N Stusser
Magnetism And Magnetic Structures Of Prmn2ge2-Xsix, Jianli Wang, S J. Campbell, M Hofmann, S J. Kennedy, R Zeng, M Md Din, S X. Dou, A Arulraj, N Stusser
Australian Institute for Innovative Materials - Papers
The structural and magnetic properties of seven PrMn2Ge2-xSix compounds with Si concentrations in the range x = 0.0-2.0 have been investigated by x-ray diffraction, magnetic (5- 350 K), differential scanning calorimetry (300-500 K) and neutron diffraction (3-480 K) measurements. Replacement of Ge by Si leads to a contraction of the unit cell and significant modifications to the magnetic states-a crossover from ferromagnetism at room temperature for Ge-rich compounds to antiferromagnetism for Si-rich compounds. The compositional dependence of the room temperature lattice parameters exhibits non-linear behaviour around x = 1.2, reflecting the presence of magnetovolume effects. Re-entrant ferromagnetism has been observed …
Enhancing Superconducting Properties Of Mgb2 Pellets By Addition Of Amorphous Magnetic Ni-Co-B Nanoparticles, Mislav Mustapic, Josip Horvat, Md Shahriar Hossain, Zeljko Skoko, S X. Dou
Enhancing Superconducting Properties Of Mgb2 Pellets By Addition Of Amorphous Magnetic Ni-Co-B Nanoparticles, Mislav Mustapic, Josip Horvat, Md Shahriar Hossain, Zeljko Skoko, S X. Dou
Australian Institute for Innovative Materials - Papers
Amorphous magnetic Ni-Co-B nanoparticles with an average size of 5 nm were added to precursor powders of MgB2 superconductor. The preparation procedure for MgB2 pellets was optimized for obtaining the best critical current density (Jc) at elevated magnetic fields. Addition of Ni-Co-B decreases the Jc for heat treatment of precursor powders at 650 ° C. Heat treatments at 770 ° C and higher improve Jc at 20 and 5 K. This improvement occurs at both temperatures through the increase of the effective connectivity between MgB2 crystals. Vortex pinning was enhanced at 5 K, but not at 20 K. Ni-Co-B nanoparticles …
Magnetic Field Induced Discontinuous Spin Reorientation In Erfeo3 Single Crystal, Hui Shen, Zhenxiang Cheng, Fang Hong, Jiayue Xu, Shujuan Yuan, Shixun Cao, Xiaolin Wang
Magnetic Field Induced Discontinuous Spin Reorientation In Erfeo3 Single Crystal, Hui Shen, Zhenxiang Cheng, Fang Hong, Jiayue Xu, Shujuan Yuan, Shixun Cao, Xiaolin Wang
Australian Institute for Innovative Materials - Papers
The spin reorientation of ErFeO3 that spontaneously occurs at low temperature has been previously determined to be a process involving the continuous rotation of Fe3þ spins. In this work, the dynamic process of spin reorientation in ErFeO3 single crystal has been investigated by AC susceptibility measurements at various frequencies and static magnetic fields. Interestingly, two completely discontinuous steps are induced by a relatively large static magnetic field due to the variation in the magnetic anisotropy during this process. It provides deeper insights into the intriguing magnetic exchange interactions which dominate the sophisticated magnetic phase transitions in the orthoferrite systems.
Magnetic Properties And Microstructures Of Iron Oxide@Mesoporous Silica Core-Shell Composite For Applications In Magnetic Dye Separation, Weichang Hao, Yang Xi, Jingwei Hu, Tianmin Wang, Yi Du, X L. Wang
Magnetic Properties And Microstructures Of Iron Oxide@Mesoporous Silica Core-Shell Composite For Applications In Magnetic Dye Separation, Weichang Hao, Yang Xi, Jingwei Hu, Tianmin Wang, Yi Du, X L. Wang
Australian Institute for Innovative Materials - Papers
"In this report, hollow mesoporous silica (HMS) and iron oxide-hollow mesoporous silica (FexOy@HMS) core-shell composite were prepared by a one-step facile fabrication method. Transmission electron microscopy, X-ray diffraction, N-2 adsorption-desorption isotherms, and vibrating sample magnetometer were used to characterize the morphology, microstructure, and magnetic properties of the HMS and core-shell composite. The magnetic separability of FexOy@HMS core-shell composite was tested in Rhodamine B (Rh. B) dye solution. The results indicate that the core-shell composite can absorb Rh. B dyes molecules effectively up to 90.1%. (C) 2012 American Institute of Physics. [doi:10.1063/1.3670049]"
Magnetic And Superconducting Properties Of Spin-Fluctuation-Limited Superconducting Nanoscale Vnx, R Zeng, J Liu, G Du, W. X. Li, J Wang, J Horvat, S X. Dou
Magnetic And Superconducting Properties Of Spin-Fluctuation-Limited Superconducting Nanoscale Vnx, R Zeng, J Liu, G Du, W. X. Li, J Wang, J Horvat, S X. Dou
Australian Institute for Innovative Materials - Papers
"VNx nanoparticles and nanowires have been prepared by nitrifying V2O5 nanoparticles (NP) and nanowires (NW). The V2O5 NP and NW were synthesized by a facile hydrothermal method. Magnetic susceptibility (chi) and magnetization measurements showed long range superconducting ordering (LRSO) at the temperature of 5.8 K for NW, but there was no observation of LRSO (at least down to 2 K) for the NP sample, which is a much lower temperature than for the corresponding bulk, while both NP and NW showed the absence of long range magnetic ordering, at least down to 2 K. However, the chi data showed that …
The Magnetic Structure Of An Epitaxial Bimn 0.5fe 0.5o 3 Thin Film On Srtio 3 (001) Studied With Neutron Diffraction, David Laurence Cortie, A Pj Stampfl, F Klose, Y Du, Xiaolin Wang, H Zhao, H Kimura, Z Cheng
The Magnetic Structure Of An Epitaxial Bimn 0.5fe 0.5o 3 Thin Film On Srtio 3 (001) Studied With Neutron Diffraction, David Laurence Cortie, A Pj Stampfl, F Klose, Y Du, Xiaolin Wang, H Zhao, H Kimura, Z Cheng
Australian Institute for Innovative Materials - Papers
High-angle neutron diffraction was used to directly reveal the atomic-scale magnetic structure of a single-crystalline BiMn 0.5 Fe 0.5 O 3 thin film deposited on a SrTiO 3 (001) substrate. The BiMn 0.5 Fe 0.5 O 3 phase exhibits distinctive magnetic properties that differentiate it from both parent compounds: BiFeO 3 and BiMnO 3. A transition to long-range G-type antiferromagnetism was observed below 120 K with a (1 2 1 2 1 2) propagation vector. A weak ferromagnetic behavior was measured at low temperature by superconducting quantum interference device (SQUID) magnetometry. There is no indication of the spin cycloid, known …
Experimental Investigation Of The Vibration Characteristics Of A Magnetorheological Elastomer Sandwich Beam Under Non-Homogeneous Small Magnetic Fields, Guoliang Hu, Miao Guo, Weihua Li, Haiping Du, Gursel Alici
Experimental Investigation Of The Vibration Characteristics Of A Magnetorheological Elastomer Sandwich Beam Under Non-Homogeneous Small Magnetic Fields, Guoliang Hu, Miao Guo, Weihua Li, Haiping Du, Gursel Alici
Faculty of Informatics - Papers (Archive)
In this study, a magnetorheological elastomer (MRE) was manufactured and tested, and a MRE sandwich beam was also fabricated from a MRE between two thin aluminum layers. An experimental test rig was set up to investigate the vibration response of the MRE sandwich beam under a non-homogeneous magnetic field. The experimental results show that the first natural frequency of the MRE sandwich beam decreased as the magnetic field applied to the beam was moved from the clamped end of the beam to the free end of the beam. It is also noted that the MRE sandwich beam had the capability …
Magnetic Properties Of Ho2fe17-Xmnx - Influence Of Mn Substitution, Jianli Wang, Stewart J. Campbell, A J Studer, S J. Kennedy, Rong Zeng
Magnetic Properties Of Ho2fe17-Xmnx - Influence Of Mn Substitution, Jianli Wang, Stewart J. Campbell, A J Studer, S J. Kennedy, Rong Zeng
Australian Institute for Innovative Materials - Papers
The structural and magnetic properties of Ho2Fe17−xMnx (x=0-5) have been investigated by x-ray diffraction, Mössbauer spectroscopy and DC magnetization measurements (0-5 T) over the temperature range 4.5-350 K. Similar to other ferrimagnetic R2Fe17-xMnx systems, the unit cell volume generally increases with Mn content other than for low Mn values where a slight maximum is detected around x ∼ 0.5. The nature of the magnetic phase transitions around TC is shown by Arrot plot analysis to be second order for all samples. The Curie temperature remains essentially unchanged …
Magnetic Flux Penetration In Polycrystalline Smfeo0.75f0.2as, Zhi W. Lin, Yong Jian Li, Jian G. Zhu, Youguang Guo, Xiaolin Wang
Magnetic Flux Penetration In Polycrystalline Smfeo0.75f0.2as, Zhi W. Lin, Yong Jian Li, Jian G. Zhu, Youguang Guo, Xiaolin Wang
Australian Institute for Innovative Materials - Papers
The recently discovered Fe–As superconducting materials which show high potential ability to carry current due to their low anisotropy have attracted a great number of attentions to understand their superconductivity mechanism and explore their applications. This paper presents a method to synthesis SmFeO0.75F0.20As polycrystalline by hot press in detail. The magnetization at different temperatures and applied fields obtained by a superconducting quantum interference device are also discussed. In addition, the local magnetization process is presented by magneto-optical imaging technique at the conditions of zero-field-cooling and field-cooling. It is found that the collective magnetization process …
Structure, Magnetic, And Thermal Properties Of Nd1-Xlaxcro3 (0 ≤ X ≤ 1.0), Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Structure, Magnetic, And Thermal Properties Of Nd1-Xlaxcro3 (0 ≤ X ≤ 1.0), Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
Perovskite-type Nd1−xLaxCrO3(0 ≤ x ≤1.0) polycrystalline samples were synthesized using solid state reaction. Structural studies indicate that the lattice parameters, metal–oxygen bond lengths, and angles of Nd1−xLaxCrO3 strongly depend on the La content. Two magnetic transition temperatures, Cr3+ antiferromagnetic ordering temperature (TN) and the spin reorientation phase transition temperature (TSRPT), have been observed in the M-T curves. The increase in TN and decrease in TSRPT with increasing x value can be explained by the change in the magnetic interactions due to La …
Magnetic Properties Of La Doped Bi2femno6 Ceramic And Film, Hongyang Zhao, Hideo Kimura, Zhenxiang Cheng, Xiaolin Wang, Kiyoshi Ozawa, Takashi Nishida
Magnetic Properties Of La Doped Bi2femno6 Ceramic And Film, Hongyang Zhao, Hideo Kimura, Zhenxiang Cheng, Xiaolin Wang, Kiyoshi Ozawa, Takashi Nishida
Australian Institute for Innovative Materials - Papers
We present a comprehensive study of the magnetic properties for La doped Bi2FeMnO6 (LBFM) ceramic and film which was first deposited on (100) SrTiO3 substrate by pulsed laser deposition method. The LBFM film is antiferromagnetic or weak ferrimagnetic at room temperature and it shows clear magnetic anisotropy. But it is not sure whether the spin-glass behavior is present in LBFM film because of the influence from substrate. Compared to the film, LBFM ceramic shows different magnetic properties. It has a lower TN and all the observations indicate that LBFM ceramic shows spin-glass behavior.
Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Lanthanum Doped Multiferroic Dyfeo3: Structural And Magnetic Properties, Yi Du, Zhenxiang Cheng, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
Lanthanum doped multiferroic DyFeO3 was synthesized by solid state reaction. X-ray diffraction and refinement show that the lattice parameters of Dy1−xLaxFeO3 increase linearly with the La content. Raman spectroscopy reveals that the short-range force constant in Dy1−xLaxFeO3 is decreased by La3+ ion substitution. The spin reorientation phase transition temperature (TSRPT) is observed to decrease along with the doping level. The antiferromagnetic ordering temperature TN of Fe3+ ions is depressed with increasing doping level. Both decreasing TSRPT and decreasing TN indicate that Fe–Dy and Fe–Fe …
Giant Magnetic Entropy Change In Colossal Magnetoresistance In La0.7ca0.3mno3 Material In Low Field, Jyotish Debnath, Rong Zeng, Jung Ho Kim, S X. Dou
Giant Magnetic Entropy Change In Colossal Magnetoresistance In La0.7ca0.3mno3 Material In Low Field, Jyotish Debnath, Rong Zeng, Jung Ho Kim, S X. Dou
Australian Institute for Innovative Materials - Papers
The structural, magnetic, and magnetocaloric properties of the manganite La0.7Ca0.3MnO3 have been studied. Change in the giant magnetic entropy was observed without any noticeable magnetic hysteresis but with small thermal hysteresis losses. We observed a first order magnetic phase transition around 251 K. The magnetic entropy change observed in this work is estimated to be 5.27 J/kg K for field changes from 0 to 1.5 T based on magnetization measurements. This value is about twice as large as those for other perovskite manganites and is even larger than for Gd-based magnetic materials at low fields. …
Magnetic Properties Of Bi2femno6: A Multiferroic Material With Double-Perovskite Structure, Yi Du, Zhenxiang Cheng, S X. Dou, Xiaolin Wang, Hua Zhao, Hideo Kimura
Magnetic Properties Of Bi2femno6: A Multiferroic Material With Double-Perovskite Structure, Yi Du, Zhenxiang Cheng, S X. Dou, Xiaolin Wang, Hua Zhao, Hideo Kimura
Australian Institute for Innovative Materials - Papers
Single phase Bi2FeMnO6 was synthesized on Si substrates by an electrospray method. Three peaks were observed in the temperature dependence of magnetization curve, which is attributed to the inhomogeneous distribution of Fe3+ and Mn3+. The observed magnetic peaks at 150 K, 260 K, and 440 K correspond to orderings of the ferrimagnetic Fe–O–Mn, and antiferromagnetic Mn–O–Mn and Fe–O–Fe, respectively. Heat capacity measurements were carried out to confirm these magnetic transitions. The Debye temperature of Bi2FeMnO6 is 339 K, calculated from Debye–Einstein fitting.
Magnetic Phase Transition In Mnfep0.5as0.4si 0.1, Jianli Wang, Stewart J. Campbell, O Tegus, E Bruck, S X. Dou
Magnetic Phase Transition In Mnfep0.5as0.4si 0.1, Jianli Wang, Stewart J. Campbell, O Tegus, E Bruck, S X. Dou
Australian Institute for Innovative Materials - Papers
We have carried out a detailed investigation of the magnetic phase transition in MnFeP0.5As0.4Si0.1. Temperature hysteresis has been observed in the variable temperature magnetization curves (Bappl = 0.01 T) with TC W ~ 302 K on warming and TC C ~ 292 K on cooling. The first order nature of this transition in MnFeP0.5As0.4Si0.1 is confirmed by the negative slope obtained from isotherms of M2 versus B/M around the critical temperature. Linear thermal expansion measurements reveal a large volume change, ΔV/V∼8.7×10-3, at the …
Magnetotransport Of La0.70ca0.3-Xsrxmno3(Ag): A Potential Room Temperature Bolometer And Magnetic Sensor, V P. Awana, Rahul Tripathi, Neeraj Kumar, H Kishan, G V. Bhalla, Rong Zeng, L.S Sharth Chandra, V Ganesan, H U. Habermeier
Magnetotransport Of La0.70ca0.3-Xsrxmno3(Ag): A Potential Room Temperature Bolometer And Magnetic Sensor, V P. Awana, Rahul Tripathi, Neeraj Kumar, H Kishan, G V. Bhalla, Rong Zeng, L.S Sharth Chandra, V Ganesan, H U. Habermeier
Australian Institute for Innovative Materials - Papers
Here we report the optimized magnetotransport properties of polycrystalline La0.70Ca0.3−xSrxMnO3 and their composites with Ag. The optimization was carried out by varying the Sr and Ag contents simultaneously to achieve large temperature coefficient of resistance (TCR) as well as low field magnetoresistance (MR) at room temperature. Sharpest paramagnetic (PM)-ferromagnetic (FM) and insulator-metal (IM) transition is observed in the vicinity of the room temperature (TC≈300 K ≈TIM) for the composition La0.70Ca0.20Sr0.10MnO3:Ag0.20. Partial substitution of larger Sr2+ ions at the …
A Sign Of Field-Induced First Order Magnetic State Transition And Giant Reversible Magnetocaloric Effect In Cobalt Hydroxide Nanosheets, Precious Shamba, Rong Zeng, J Q Wang, S X. Dou
A Sign Of Field-Induced First Order Magnetic State Transition And Giant Reversible Magnetocaloric Effect In Cobalt Hydroxide Nanosheets, Precious Shamba, Rong Zeng, J Q Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
We report the synthesis of β−Co(OH)2 nanosheets using microwave assisted hydrothermal and conventional chemical reaction methods. A magnetic transition at an onset temperature, T1 ~ 96 K, and a sign of antiferromagnetic state transition at the Néel temperature, TN=9~10 K, can be determined from M-T curves and M-H curves magnetic properties investigation. It is found that a sign of field-induced first order transition below 9 K, act as a role of reversing the magnetocaloric effect from negative to positive value. The large reversible magnetic-entropy change (∆SM) of 17 J/kg K around 11 K for …
Concurrent Magnetic And Metal-Insulator Transitions In Eu1-Xsmxb6, J. E. Bunder, Sung-Ik Lee, Hsiu-Hau Lin, S. Yeo, Myung-Hwa Jung
Concurrent Magnetic And Metal-Insulator Transitions In Eu1-Xsmxb6, J. E. Bunder, Sung-Ik Lee, Hsiu-Hau Lin, S. Yeo, Myung-Hwa Jung
Faculty of Informatics - Papers (Archive)
The effects of magnetic doping on a EuB6 single crystal were investigated based on magnetic and transport measurements. A modest 5% Sm substitution for Eu changes the magnetic and transport properties dramatically and gives rise to concurrent ant--ferromagnetic and metal-insulator transtitions (MITs) from ferromagnetic MIT for EuB6.
Structure, Ferroelectric Properties, And Magnetic Properties Of The La-Doped Bismuth Ferrite, Zhenxiang Cheng, Aihua Li, Xiaolin Wang, S X. Dou, Kiyoshi Ozawa, Hideo Kimura, S Zhang, Thomas R. Shrout
Structure, Ferroelectric Properties, And Magnetic Properties Of The La-Doped Bismuth Ferrite, Zhenxiang Cheng, Aihua Li, Xiaolin Wang, S X. Dou, Kiyoshi Ozawa, Hideo Kimura, S Zhang, Thomas R. Shrout
Australian Institute for Innovative Materials - Papers
Bi1-xLaxFeO3 ceramics with x=0, 0.1, 0.2, and 0.3 have been synthesized by solid state reaction, starting from metal oxides. A series of structure transformations is found to depend upon the doping level. Below 10% La doping, Bi1-xLaxFeO3 maintains the rhombohedral structure of BiFeO3. However, for Bi0.8La0.2FeO3 and Bi0.7La0.3FeO3, the structures change to the orthorhombic and tetragonal, respectively. La doping significantly reduces electric leakage and leads to successful observation of electrical polarization hysteresis loops. Doping with La also …
Dielectric, Magnetic, And Magnetotransport Properties In Sr Doped Two-Dimensional Re2coo4 (Re=Pr,Eu) Compounds, Qiwen Yao, Xiaolin Wang, S X. Dou
Dielectric, Magnetic, And Magnetotransport Properties In Sr Doped Two-Dimensional Re2coo4 (Re=Pr,Eu) Compounds, Qiwen Yao, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
In this work, we report on the studies of dielectric, magnetic, and magnetotransport properties of Sr doped RE2-xSrxCoO4 (RE=Pr or Eu, x=0.25-1.5). These compounds were systematically studied in terms of structure, magnetic, magnetotransport, and dielectric constant measurements. Rietveld refinement indicated that these compounds crystallized in K2NiF4-type structure with space group I4/mmm. Lattice parameters increase with Sr doping level. The system changes from paramagnetic to ferromagnetic with increasing Sr doping level and finally becomes ferromagnetic with TC of 230 K for Pr0.75Sr1.25CoO4 and …
Influence Of Inductance Variation On Performance Of A Permanent Magnet Claw Pole Soft Magnetic Composite Motor, Youguang Guo, Jian Zhu, Zhi Lin, Haiyan Lu, Xiaolin Wang, Jiaxin Chen
Influence Of Inductance Variation On Performance Of A Permanent Magnet Claw Pole Soft Magnetic Composite Motor, Youguang Guo, Jian Zhu, Zhi Lin, Haiyan Lu, Xiaolin Wang, Jiaxin Chen
Australian Institute for Innovative Materials - Papers
Winding inductance is an important parameter in determining the performance of electrical machines, particularly those with large inductance variation. This paper investigates the influence of winding inductance variation on the performance of a three-phase three-stack claw pole permanent magnet motor with soft magnetic composite (SMC) stator by using an improved phase variable model. The winding inductances of the machine are computed by using a modified incremental energy method, based on three-dimensional nonlinear time-stepping magnetic field finite element analyses. The inductance computation and performance simulation are verified by the experimental results of an SMC claw pole motor prototype.
Magnetic Anisotropy Of Naxcoo2 Single Crystals, Dapeng Chen, Xiaolin Wang, C T Lin, S X. Dou
Magnetic Anisotropy Of Naxcoo2 Single Crystals, Dapeng Chen, Xiaolin Wang, C T Lin, S X. Dou
Australian Institute for Innovative Materials - Papers
We report the magnetic properties of single crystals of NaxCoO2 (x=0.42, 0.82, and 0.87). The magnetic susceptibility measurements revealed considerable anisotropy along H parallel to ab and H parallel to c for the as-grown single crystals. It was found that an antiferromagnetic transition with a Neel temperature T-N=21 K occurred for the x=0.82 sample, and there was a paramagnetic phase for the x=0.87 sample over a wide temperature range from 2 to 300 K, but the sample with x=0.42 shows a monotonic increase of chi with increasing temperature above similar to 100 K. In addition, …
Spin-Polarized Transport In Dilute Magnetic Semiconductor Tunnel Junctions, J E. Bunder
Spin-Polarized Transport In Dilute Magnetic Semiconductor Tunnel Junctions, J E. Bunder
Faculty of Informatics - Papers (Archive)
No abstract provided.
Kinetic Roughening Of Magnetic Flux Penetration In Mgb2 Thin Films, Andrea Lucarelli, Stephanie Hummert, Andrea Chaney, Gunter Lupke, Brian Moeckly, Yue Zhao, S X. Dou
Kinetic Roughening Of Magnetic Flux Penetration In Mgb2 Thin Films, Andrea Lucarelli, Stephanie Hummert, Andrea Chaney, Gunter Lupke, Brian Moeckly, Yue Zhao, S X. Dou
Australian Institute for Innovative Materials - Papers
Time-resolved magneto-optical studies are performed on MgB2 thin film samples grown by in situ pulsed laser deposition and in situ reactive deposition technique. The latter reveal dendritic avalanche-free flux penetration. The kinetic roughening of magnetic flux penetration is studied for applied ac current. Dynamic scaling laws determined for both static field and ac current are consistent with the directed percolation depinning model, placing the vortex dynamics in MgB2 in the same universality class as YBCO and Nb.
Room Temperature Magnetic-Field Manipulation Of Electrical Polarization In Multiferroic Thin Film Composite Bifeo3/La2/3ca1/3mno3, Zhenxiang Cheng, Xiaolin Wang
Room Temperature Magnetic-Field Manipulation Of Electrical Polarization In Multiferroic Thin Film Composite Bifeo3/La2/3ca1/3mno3, Zhenxiang Cheng, Xiaolin Wang
Australian Institute for Innovative Materials - Papers
The electrical polarization in an epitaxially BiFeO3 film grown on La2/3Ca1/3MnO3/SrTiO3 is observed to be enhanced greatly by a magnetic field at room temperature. The simultaneous ferromagnetic order and ferroelectric polarization shown by the BiFeO3 film causes the strong coupling of the magnetic and ferroelectric domains in the BiFeO3 films. It was proposed that the activation energy for the electrical polarization domains switching is reduced by the application of a magnetic field. As a result, the electrical polarization that can be switched by an electrical field is increased by the …
Single-Crystal Growth And Anisotropic Magnetic Properties Of Nonstoichiometric Three-Layer Sodium Cobalt Oxides, Dapeng Chen, Xiaolin Wang, C T Lin, S X. Dou
Single-Crystal Growth And Anisotropic Magnetic Properties Of Nonstoichiometric Three-Layer Sodium Cobalt Oxides, Dapeng Chen, Xiaolin Wang, C T Lin, S X. Dou
Australian Institute for Innovative Materials - Papers
Large single crystals of α-NaxCoO2 (x=0.91, 0.92, and 0.93) have been successfully fabricated by using the traveling solvent floating zone method. Details on the crystal growth are discussed. The crystal structures were characterized using powder x-ray diffraction and Rietveld refinement. The magnetic susceptibility measurements show that the magnetic properties depend strongly on x. The compound was found to be antiferromagnetic at TN ≈ 20 K for x=0.91 and x=0.92, and paramagnetic for x=0.93. The in-plane and out-of-plane anisotropies were observed for the x=0.91 crystals. In addition, the derived anisotropic g-factor ratios (gab /gc) …
Josephson-Vortex Flow Resistance In Bi2sr2ca2cu3oy Single Crystals And Its Possible Application In The Manipulation Of Spin And Charge Textures In Diluted Magnetic Semiconductors, Xiaolin Wang, C T Lin, B Liang, S Yu, S Ooi, K Hirata, S Y Ding, Dongqi Shi, S X. Dou, Zhi W. Lin, Jian G. Zhu
Josephson-Vortex Flow Resistance In Bi2sr2ca2cu3oy Single Crystals And Its Possible Application In The Manipulation Of Spin And Charge Textures In Diluted Magnetic Semiconductors, Xiaolin Wang, C T Lin, B Liang, S Yu, S Ooi, K Hirata, S Y Ding, Dongqi Shi, S X. Dou, Zhi W. Lin, Jian G. Zhu
Australian Institute for Innovative Materials - Papers
In this work, the flow of the Josephson vortices (JVs) has been studied for the highly anisotropic Bi2Sr2Ca2Cu3Oy (Bi2223) single crystals. A giant flow of JVs or giant positive magnetoresistance (MR) of over 500%-2000% was obtained in fields of 0.1-5 T and remained almost constant over a wide temperature range from 110 down to 4 K, in contrast to superconducting vortices (SVs), which only produced MR in the vicinity of Tc. The flow of the JVs is expected to be much faster than that of SVs. It is proposed …
Band Structures, Magnetic Properties, And Enhanced Magnetoresistance In The High Pressure Phase Of Gd And Y Doped Two-Dimensional Perovskite Sr2coo4 Compounds, Xiaolin Wang, E Takayama-Muromachi, S X. Dou, Zhenxiang Cheng
Band Structures, Magnetic Properties, And Enhanced Magnetoresistance In The High Pressure Phase Of Gd And Y Doped Two-Dimensional Perovskite Sr2coo4 Compounds, Xiaolin Wang, E Takayama-Muromachi, S X. Dou, Zhenxiang Cheng
Australian Institute for Innovative Materials - Papers
The authors present their studies on the band structures and on the magnetic and magnetotransport properties of the high pressure phase of Sr2-xRExCoO4 [rare earth (RE)=Gd and Y, x=0.1-0.5] compounds which were synthesized by a high pressure and high temperature technique. The authors found that as x increases, the magnetoresistance {(PH-P0)/p0} increases up to -17% at 5 K and 7 T, which is 2.5 times higher than that for undoped Sr2CoO4, although the ferromagnetic transition drops from 255 to 200 K for the Gd doping with x=0.3. …