High coercivity in Co-Cr films induced by nitrogen gas addition during room temperature sputter-deposition

The emergence of Dilute Magnetic Semiconductors (DMS) with a potentials for spintronic application have attracted much researches attention, special consideration has been given to ZnO semiconductor material due to its wide band gap of 3.37 eV, large exciting binding energy of 60 meV, moreover, its ferromagnetic behavior at room temperature when doped with transition metals. MxZn1-xO (M = Fe or Ni) nanoparticles were synthesized by microwave assisted synthesis method calcined at 600°C. The structural, morphological and magnetic properties of these nanoparticles were studied using X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Vibrating Sample Magnetometer (VSM) respectively. Single phase Wurtzite hexagonal crystal structure was observed for the undoped and Fe doped ZnO nanoparticles with no any impurity, whereas Ni doped ZnO nanoparticles shows the formation of NiO impurities. The magnetic measurement reveals a diamagnetic behavior for the undoped ZnO meanwhile a clear room temperature ferromagnetism was observed for both Fe and Ni doped ZnO. Fe doped ZnO present a high saturation magnetization compared to Ni doped ZnO. However, Ni doped ZnO present high coercivity. The research was confirmed that Fe doped ZnO material will be good material combination for spintronic applications.

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Low Temperature Expansion of Polysulfide Rubbers

Rubber Chemistry and Technology ◽

10.5254/1.3544834 ◽

1966 ◽

Vol 39 (2) ◽

pp. 211-216

Author(s):

B. A. Hunter ◽

M. J. Kleinfeld

Keyword(s):

Room Temperature ◽

Liquid Mixture ◽

Cumene Hydroperoxide ◽

Polymer Chains ◽

Nitrogen Gas ◽

Blowing Agents ◽

Disulfide Linkages ◽

Novel Method ◽

Rubber Product ◽

Liquid Polysulfide Rubbers

Abstract A novel method for producing a cellular cured rubber product at room temperature has been developed. Pourable liquid polysulfide polymers are treated with a conventional oxidizing curative and selected water-sensitive or oxidation-sensitive blowing agents. Standing at ambient temperature the viscous liquid mixture gradually “rises” and cures to form a finely porous cellular rubber product. Conventional curatives employed include oxidizing agents such as lead peroxide and cumene hydroperoxide. These convert terminal or pendant thiol groups in the polysulfide polymer chains to chain-connecting disulfide linkages. Water is a byproduct of the curing reaction. In the presence of water-sensitive blowing agents such as, (1) metal salts of azodicarboxylic acid or, (2) metal hydride compounds the water produced in the cure reacts to form copious amounts of nitrogen or of hydrogen. Alternatively, oxidation-sensitive blowing agents such as p, p′-oxybis-(benzene sulfonyl hydrazide) react directly with the oxidizing curative to form nitrogen gas. The blowing reactions are concurrent with cure and efficient and controllable expansion can be achieved. The unique process offers possible economies and special properties in applications of liquid polysulfide rubbers as potting compounds, joint sealants, solvent resistant forms, and cold casting compounds.

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High Coercivity of Oleic Acid Capped CoFe2O4Nanoparticles at Room Temperature

The Journal of Physical Chemistry B ◽

10.1021/jp810975v ◽

2009 ◽

Vol 113 (27) ◽

pp. 9070-9076 ◽

Cited By ~ 161

Author(s):

Mukta V. Limaye ◽

Shashi B. Singh ◽

Sadgopal K. Date ◽

Deepti Kothari ◽

V. Raghavendra Reddy ◽

...

Keyword(s):

Oleic Acid ◽

Room Temperature ◽

High Coercivity

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Mn-Bi Magnetic Powders With High Coercivity and Magnetization at Room Temperature

IEEE Transactions on Magnetics ◽

10.1109/tmag.2012.2201146 ◽

2012 ◽

Vol 48 (11) ◽

pp. 3641-3643 ◽

Cited By ~ 21

Author(s):

Chins Chinnasamy ◽

Melania M. Jasinski ◽

Aaron Ulmer ◽

Wanfeng Li ◽

George Hadjipanayis ◽

...

Keyword(s):

Room Temperature ◽

High Coercivity

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Influence of the Annealing Ambient on Structural and Optical Properties of Rare Earth Implanted GaN

MRS Proceedings ◽

10.1557/proc-0892-ff23-15 ◽

2005 ◽

Vol 892 ◽

Cited By ~ 2

Author(s):

Katharina Lorenz ◽

E. Nogales ◽

R. Nédélec ◽

J. Penner ◽

R. Vianden ◽

...

Keyword(s):

Optical Properties ◽

Rare Earth ◽

Room Temperature ◽

Rutherford Backscattering Spectrometry ◽

Strong Increase ◽

Structural And Optical Properties ◽

Nitrogen Gas ◽

Higher Temperature ◽

The Eu ◽

The Rare Earth

AbstractGaN films were implanted with Er and Eu ions and rapid thermal annealing was performed at 1000, 1100 and 1200 °C in vacuum, in flowing nitrogen gas or a mixture of NH3 and N2. Rutherford backscattering spectrometry in the channeling mode was used to study the evolution of damage introduction and recovery in the Ga sublattice and to monitor the rare earth profiles after annealing. The surface morphology of the samples was analyzed by scanning electron microscopy and the optical properties by room temperature cathodoluminescence (CL). Samples annealed in vacuum and N2 already show the first signs of surface dissociation at 1000 °C. At higher temperature, Ga droplets form at the surface. However, samples annealed in NH3 + N2 exhibit a very good recovery of the lattice along with a smooth surface. These samples also show the strongest CL intensity for the rare earth related emissions in the green (for Er) and red (for Eu). After annealing at 1200 °C in NH3+N2 the Eu implanted sample reveals the channeling qualities of an unimplanted sample and a strong increase of CL intensity is observed.

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InN PHOTOCONDUCTORS ON DIFFERENT ORIENTATIONS OF Si SUBSTRATES

International Journal of Modern Physics B ◽

10.1142/s0217979212501378 ◽

2012 ◽

Vol 26 (31) ◽

pp. 1250137 ◽

Cited By ~ 7

Author(s):

M. AMIRHOSEINY ◽

Z. HASSAN ◽

S. S. NG ◽

L. S. CHUAH ◽

M. A. AHMAD ◽

...

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Ohmic Contact ◽

Room Temperature ◽

Thermal Evaporation ◽

Indium Nitride ◽

Rf Sputtering ◽

Nitrogen Gas ◽

Si Substrates ◽

Current Voltage

We have fabricated photoconductors of indium nitride (InN) grown by radio frequency (RF) sputtering. The InN thin films were deposited on Si (100), Si (110) and Si (111) substrates at room temperature. The Ag/Al contact has been deposited by thermal evaporation in vacuum (10-5 Torr ) and then annealed under the flowing of the nitrogen gas environment in order to relieve stress and also induce any favorable reactions between metals and the semiconductor. Current–voltage (I–V) measurements after heat treatment at 400°C were carried out for samples in dark and illumination conditions. It was found that Ag/Al formed a good ohmic contact on top of InN . In addition, the characteristics of the contacts were significantly affected by the orientation of substrates.

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Magnetic Properties of FePt Nanoparticles Prepared by Sonoelectrodeposition

Journal of Nanomaterials ◽

10.1155/2012/801240 ◽

2012 ◽

Vol 2012 ◽

pp. 1-4 ◽

Cited By ~ 7

Author(s):

Nguyen Hoang Nam ◽

Nguyen Thi Thanh Van ◽

Nguyen Dang Phu ◽

Tran Thi Hong ◽

Nguyen Hoang Hai ◽

...

Keyword(s):

Magnetic Properties ◽

Saturation Magnetization ◽

Metallic Nanoparticles ◽

Room Temperature ◽

Cathode Surface ◽

High Coercivity ◽

Fept Nanoparticles ◽

Promising Technique ◽

Structural And Magnetic Properties

Sonoelectrodeposition is a useful technique to make metallic nanoparticles, using ultrasound during electrodeposition to remove nanoparticles as they grow on the cathode surface. This paper reports some structural and magnetic properties of FePt nanoparticles prepared by this method. The as-prepared Fe45Pt55nanoparticles were ferromagnetic at room temperature. Upon annealing at 700°C for 1 h under H2atmosphere, the saturation magnetization and the coercivity of the nanoparticles were improved significantly. The annealed nanoparticles showed a high coercivity of 13.5 kOe at 2 K and of 9 kOe at room temperature. Sonoelectrodeposition is a promising technique to make large quantity of FePt nanoparticles.

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Reactive Sputtering Growth and Characterizations of InN Thin Films on Si Substrates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.545.290 ◽

2012 ◽

Vol 545 ◽

pp. 290-293

Author(s):

Maryam Amirhoseiny ◽

Hassan Zainuriah ◽

Ng Shashiong ◽

Mohd Anas Ahmad

Keyword(s):

Thin Films ◽

Room Temperature ◽

Rf Magnetron Sputtering ◽

Rf Power ◽

X Ray Diffraction ◽

Nitrogen Gas ◽

X Ray ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force

We have studied the effects of deposition conditions on the crystal structure of InN films deposited on Si substrate. InN thin films have been deposited on Si(100) substrates by reactive radio frequency (RF) magnetron sputtering method with pure In target at room temperature. The nitrogen gas pressure, applied RF power and the distance between target and substrate were 2×10-2 Torr, 60 W and 8 cm, respectively. The effects of the Ar–N2 sputtering gas mixture on the structural properties of the films were investigated by using scanning electron microscope, energy-dispersive X-ray spectroscopy, atomic force microscopy and X-ray diffraction techniques.

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Holmium induced enhanced functionality at room temperature and structural phase transition at high temperature in bismuth ferrite nanoparticles

Journal of Materials Chemistry C ◽

10.1039/c5tc02941d ◽

2016 ◽

Vol 4 (4) ◽

pp. 780-792 ◽

Cited By ~ 20

Author(s):

Smita Chaturvedi ◽

Rabindranath Bag ◽

Vasant Sathe ◽

Sulabha Kulkarni ◽

Surjeet Singh

Keyword(s):

Phase Transition ◽

High Temperature ◽

High Temperatures ◽

Structural Phase Transition ◽

Room Temperature ◽

Bismuth Ferrite ◽

Structural Phase ◽

Ferrite Nanoparticles ◽

High Coercivity ◽

Remnant Magnetization

Ho-doped sample simultaneously exhibits high-coercivity and enhanced remnant magnetization with a polar R3c symmetry at room temperature. The onset of R3c to Pnma phase transition is observed at high temperatures in the Ho-doped samples.

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