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2014

Magnetic

Articles 1 - 13 of 13

Full-Text Articles in Physical Sciences and Mathematics

Neutron Diffraction Study Of Mnniga2 - Structural And Magnetic Behaviour, Jianli Wang, L Ma, M Hofmann, M Avdeev, S J. Kennedy, S J. Campbell, M F. Md Din, M Hoelzel, G H. Wu, S X. Dou Jan 2014

Neutron Diffraction Study Of Mnniga2 - Structural And Magnetic Behaviour, Jianli Wang, L Ma, M Hofmann, M Avdeev, S J. Kennedy, S J. Campbell, M F. Md Din, M Hoelzel, G H. Wu, S X. Dou

Australian Institute for Innovative Materials - Papers

MnNiGa2 crystallizes in the L21 (Heusler) structure and has a ferromagnetic ordering temperature TC ∼ 192 K. Rietveld refinement of the neutron diffraction patterns indicates that the Ga atoms occupy the equivalent 8c position, while Mn and Ni share the 4a (0, 0, 0) and 4b (0.5, 0.5, 0.5) sites with a mixed occupancy of Mn and Ni atoms. It is found that that ∼83% of Mn and ∼17% Ni are located at the 4a site while ∼83% of Ni and ∼17% Mn occupy the 4b site. There is no evidence of a magneto-volume effect around TC. In agreement with …


Magnetic Transitions And The Magnetocaloric Effect In The Pr 1-Xyxmn2ge2 System, Jianli Wang, S J. Campbell, M F. Md Din, S J. Kennedy, M Hofmann Jan 2014

Magnetic Transitions And The Magnetocaloric Effect In The Pr 1-Xyxmn2ge2 System, Jianli Wang, S J. Campbell, M F. Md Din, S J. Kennedy, M Hofmann

Australian Institute for Innovative Materials - Papers

Layered rare earth compounds in the RMn2X2 series (R = rare-earth; X = Ge, Si) are of interest for potential cooling applications at lower temperatures as they enable the structural and magnetic behavior to be controlled via substitution of R, Mn, and X atoms on the 2a, 4d, and 4e sites respectively. We continue investigations of the Pr1−xYxMn2Ge2 magnetic phase diagram as functions of both composition and Mn-Mn spacing using X-ray and neutron diffraction, magnetization and differential scanning calorimetry measurements. Pr1−xYxMn2Ge2 exhibits an extended region of re-entrant ferromagnetism around x ∼ 0.5 with re-entrant ferromagnetism at inline image for Pr0.5Y0.5Mn2Ge2. …


Magnetic Properties And Magnetocaloric Effect Of Ndmn2-Xcuxsi2 Compounds, M F. Md Din, Jianli Wang, M Avdeev, Q F. Gu, R Zeng, S J. Campbell, S J. Kennedy, S X. Dou Jan 2014

Magnetic Properties And Magnetocaloric Effect Of Ndmn2-Xcuxsi2 Compounds, M F. Md Din, Jianli Wang, M Avdeev, Q F. Gu, R Zeng, S J. Campbell, S J. Kennedy, S X. Dou

Australian Institute for Innovative Materials - Papers

Structural and magnetic properties of NdMn2−x Cu xSi2 compounds (x = 0-1.0) have been investigated by high intensity x-ray and resolution neutron diffraction (3-450 K), specific heat, dc magnetization, and differential scanning calorimetry measurements. Substitution of Cu for Mn leads to an increase in the lattice parameter a but a decrease in c at room temperature. Two magnetic phase transitions have been found for NdMn2−x Cu xSi2 compounds with TN for the antiferromagnetic ordering of Mn-sublatttice and TC for the Nd-sublattice ferromagnetic ordering, respectively. TC increases significantly with increasing Cu content from 36 K at x = 0 to 100 …


Direct Evidence Of Ni Magnetic Moment In Tbni2mn-X-Ray Magnetic Circular Dichroism, D H. Yu, Meng-Jie Huang, Jianli Wang, Hui-Chia Su, Hong-Ji Lin, Chien-Te Chen, S J. Campbell Jan 2014

Direct Evidence Of Ni Magnetic Moment In Tbni2mn-X-Ray Magnetic Circular Dichroism, D H. Yu, Meng-Jie Huang, Jianli Wang, Hui-Chia Su, Hong-Ji Lin, Chien-Te Chen, S J. Campbell

Australian Institute for Innovative Materials - Papers

We have investigated the individual magnetic moments of Ni, Mn and Tb atoms in the intermetallic compound TbNi2Mn in the Laves phase (magnetic phase transition temperature TC ∼131 K) by X-ray magnetic circular dichroism (XMCD) studies at 300 K, 80 K and 20 K. Analyses of the experimental results reveal that Ni atoms at 20 K in an applied magnetic field of 1 T carry an intrinsic magnetic moment of spin and orbital magnetic moment contributions 0.53±0.01 μB and 0.05±0.01 μB, respectively. These moment values are similar to those of the maximum saturated moment of Ni element. A very small …


Platinum Dendritic Nanoparticles With Magnetic Behavior, Wenxian Li, Ziqi Sun, Dongliang Tian, Ivan P. Nevirkovets, S X. Dou Jan 2014

Platinum Dendritic Nanoparticles With Magnetic Behavior, Wenxian Li, Ziqi Sun, Dongliang Tian, Ivan P. Nevirkovets, S X. Dou

Australian Institute for Innovative Materials - Papers

Magnetic nanoparticles have attracted increasing attention for biomedical applications in magnetic resonance imaging, high frequency magnetic field hyperthermia therapies, and magnetic-field-gradient-targeted drug delivery. In this study, three-dimensional (3D) platinum nanostructures with large surface area that features magnetic behavior have been demonstrated. The well-developed 3D nanodendrites consist of plentiful interconnected nano-arms ∼4 nm in size. The magnetic behavior of the 3D dendritic Pt nanoparticles is contributed by the localization of surface electrons due to strongly bonded oxygen/Pluronic F127 and the local magnetic moment induced by oxygen vacancies on the neighboring Pt and O atoms. The magnetization of the nanoparticles exhibits a …


90° Magnetic Coupling In A Nife/Femn/Biased Nife Multilayer Spin Valve Component Investigated By Polarized Neutron Reflectometry, S J. Callori, J Bertinshaw, David L. Cortie, J W. Cai, A P. Le Brun, T Zhu, Frank Klose Jan 2014

90° Magnetic Coupling In A Nife/Femn/Biased Nife Multilayer Spin Valve Component Investigated By Polarized Neutron Reflectometry, S J. Callori, J Bertinshaw, David L. Cortie, J W. Cai, A P. Le Brun, T Zhu, Frank Klose

Australian Institute for Innovative Materials - Papers

We have observed 90° magnetic coupling in a NiFe/FeMn/biased NiFe multilayer system using polarized neutron reflectometry. Magnetometry results show magnetic switching for both the biased and free NiFe layers, the latter of which reverses at low applied fields. As these measurements are only capable of providing information about the total magnetization within a sample, polarized neutron reflectometry was used to investigate the reversal behavior of the NiFe layers individually. Both the non-spin-flip and spin-flip neutron reflectometry signals were tracked around the free NiFe layer hysteresis loop and were used to detail the evolution of the magnetization during reversal. At low …


Magnetic Properties And Magnetocaloric Effect In Layered Ndmn 1.9v0.1si2, M F. Md Din, Jianli Wang, R Zeng, Shane Kennedy, S J. Campbell, S X. Dou Jan 2014

Magnetic Properties And Magnetocaloric Effect In Layered Ndmn 1.9v0.1si2, M F. Md Din, Jianli Wang, R Zeng, Shane Kennedy, S J. Campbell, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the compounds NdMn2-xVxSi2 have been studied by x-ray and high resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9V0.1Si2 are been indicate at TC ~ 24 K and TN ~ 376 K respectively. The giant magnetocaloric effect (GMCE) around TC is found in layered NdMn1.9V0.1Si2 associated with first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc]. This behaviorhas been confirmed as contribution of the magnetostructural coupling by using neutron powder diffraction. The magnetic entropy …


A Comparative Study Of Magnetic Behaviors In Tbni2, Tbmn2 And Tbni2mn, Jianli Wang, M F. Md Din, Shane Kennedy, F Hong, Stewart J. Campbell, A J. Studer, G H. Wu, Zhenxiang Cheng, S X. Dou Jan 2014

A Comparative Study Of Magnetic Behaviors In Tbni2, Tbmn2 And Tbni2mn, Jianli Wang, M F. Md Din, Shane Kennedy, F Hong, Stewart J. Campbell, A J. Studer, G H. Wu, Zhenxiang Cheng, S X. Dou

Australian Institute for Innovative Materials - Papers

All TbNi2, TbMn2, and TbNi2Mn compounds exhibit the cubic Laves phase with AB2-type structure in spite of the fact that the ratio of the Tb to transition-metal components in TbNi2Mn is 1:3. Rietveld refinement indicates that in TbNi2Mn the Mn atoms are distributed on both the A (8a) and B (16d) sites. The values of the lattice constants were measured to be a = 14.348 Å (space group F-43 m), 7.618 Å, and 7.158 Å (space group Fd-3 m) for TbNi2, TbMn2, and TbNi2Mn, respectively. The magnetic transition temperatures TC were found to be TC = 38 K and TC …


Magnetic Transitions In Lafe13-X-Ycoysix Compounds, Jianli Wang, S J. Campbell, S J. Kennedy, P Shamba, R Zeng, S X. Dou, G H. Wu Jan 2014

Magnetic Transitions In Lafe13-X-Ycoysix Compounds, Jianli Wang, S J. Campbell, S J. Kennedy, P Shamba, R Zeng, S X. Dou, G H. Wu

Australian Institute for Innovative Materials - Papers

The magnetic properties of a set of LaFe13−x−yCoySix compounds (x = 1.6 − 2.6; y = 0, y = 1.0) have been investigated using magnetic measurements, thermal expansion, 57Fe Mössbauer spectroscopy and high resolution neutron powder diffraction methods over the temperature range 10–300 K. The natures of the magnetic transitions in these LaFe13−x−yCoySix compounds have been determined. The Curie temperatures of LaFe13−xSix were found to increase with Si content from TC = 219(5) K for Si content x = 1.6 to TC = 250(5) K for x = 2.6. Substitution of Co for Fe in LaFe10.4Si2.6 resulted in a further …


Significant Tunability Of Thin Film Functionalities Enabled By Manipulating Magnetic And Structural Nano-Domains, Igor A. Golovchanskiy, Alexey V. Pan, Sergey A. Fedoseev, Michael Higgins Jan 2014

Significant Tunability Of Thin Film Functionalities Enabled By Manipulating Magnetic And Structural Nano-Domains, Igor A. Golovchanskiy, Alexey V. Pan, Sergey A. Fedoseev, Michael Higgins

Australian Institute for Innovative Materials - Papers

The influence of laser frequency on the structure and physical properties of thin films grown by pulsed laser deposition has been studied. Different types of thin films, hard ferromagnetic FePt L10 and quasi-single crystal superconducting YBa2Cu3O7 (YBCO), have been used for demonstration of the effect. Significant structural modifications have been obtained for the films with similar thicknesses. These modifications are shown to dramatically control their corresponding properties, providing an instrumental ability for tuning the practical characteristics of the films by changing the laser frequency of their deposition. In particular, 20-fold increase of coercive field and modification of demagnetization mechanism are …


Magnetic Properties And Magnetocaloric Effect In Layered Ndmn1.9ti0.1si2, M F. Md Din, Jianli Wang, Shane J. Kennedy, Stewart J. Campbell, S X. Dou Jan 2014

Magnetic Properties And Magnetocaloric Effect In Layered Ndmn1.9ti0.1si2, M F. Md Din, Jianli Wang, Shane J. Kennedy, Stewart J. Campbell, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the NdMn1.9Ti0.1Si2 compund have been studied by high-intensity x-ray and high-resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range of 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9Ti0.1Si2 are indicated as TC ~ 22 K and TN ~ 374 K respectively. The first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc] around TC is found in layered NdMn1.9Ti0.1Si2 and is …


Spin Memristive Magnetic Tunnel Junctions With Coo-Zno Nano Composite Barrier, Qiang Li, Ting-Ting Shen, Yan-Ling Cao, Kun Zhang, Shi-Shen Yan, Yu-Feng Tian, Shi-Shou Kang, Ming-Wen Zhao, You-Yong Dai, Yan-Xue Chen, Guo-Lei Liu, Liang-Mo Mei, Xiaolin Wang, Peter Grunberg Jan 2014

Spin Memristive Magnetic Tunnel Junctions With Coo-Zno Nano Composite Barrier, Qiang Li, Ting-Ting Shen, Yan-Ling Cao, Kun Zhang, Shi-Shen Yan, Yu-Feng Tian, Shi-Shou Kang, Ming-Wen Zhao, You-Yong Dai, Yan-Xue Chen, Guo-Lei Liu, Liang-Mo Mei, Xiaolin Wang, Peter Grunberg

Australian Institute for Innovative Materials - Papers

The spin memristive devices combining memristance and tunneling magnetoresistance have promising applications in multibit nonvolatile data storage and artificial neuronal computing. However, it is a great challenge for simultaneous realization of large memristance and magnetoresistance in one nanoscale junction, because it is very hard to find a proper spacer layer which not only serves as good insulating layer for tunneling magnetoresistance but also easily switches between high and low resistance states under electrical field. Here we firstly propose to use nanon composite barrier layers of CoO-ZnO to fabricate the spin memristive Co/CoO-ZnO/Co magnetic tunnel junctions. The bipolar resistance switching ratio …


Magnetic Phase Transitions And Entropy Change In Layered Ndmn1.7cr0.3si2, M F. Md Din, Jianli Wang, S J. Campbell, A J. Studer, M Avdeev, S J. Kennedy, Q F. Gu, R Zeng, S X. Dou Jan 2014

Magnetic Phase Transitions And Entropy Change In Layered Ndmn1.7cr0.3si2, M F. Md Din, Jianli Wang, S J. Campbell, A J. Studer, M Avdeev, S J. Kennedy, Q F. Gu, R Zeng, S X. Dou

Australian Institute for Innovative Materials - Papers

A giant magnetocaloric effect has been observed around the Curie temperature, TC ∼ 42 K, in NdMn1.7Cr0.3Si2 with no discernible thermal and magnetic hysteresis losses. Below 400 K, three magnetic phase transitions take place around 380 K, 320 K and 42 K. Detailed high resolution synchrotron and neutron powder diffraction (10-400 K) confirmed the magnetic transitions and phases as follows: TN intra ∼ 380 K denotes the transition from paramagnetism to intralayer antiferromagnetism (AFl), TN inter ∼ 320 K represents the transition from the AFl structure to the canted antiferromagnetic spin structure (AFmc), while TC ∼ 42 K denotes the …