Browsing by Author "VENKATESAN, MUNUSWAMY"

Now showing items 21-40 of 42

    • M?_ssbauer spectrometry of A2FeMoO6 (A =Ca, Sr, Ba): Search for antiphase domains 

      VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID (American Physical Society, 2001)
      M?_ssbauer spectrometry was carried out in the range of temperature from 4 K to well above the Curie temperature on polycrystalline ceramics of A2FeMoO6 (A=Ca,Sr,Ba). A secondary component in all the paramagnetic or ...

    • Magnetic and electronic properties of D022-Mn3Ge (001) films 

      RODE, KARSTEN; SANVITO, STEFANO; COEY, JOHN; STAMENOV, PLAMEN; VENKATESAN, MUNUSWAMY (2012)
      Oriented thin films of Mn3Ge with the tetragonal D022structure,grown on strontium titanate substrates, exhibit a low magnetization M s?=?73?kA m?1 combined with high uniaxial anisotropyK u?=?0.91?MJ m?3 at 300?K, making ...

    • Magnetic properties of mechanically-alloyed Sm-Co nanophase hard magnets 

      VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID (IEEE, 2001)
      Highly coercive Sm14Co86 powders were prepared by mechanical alloying with a view to enhance the high temperature magnetic properties by optimizing the annealing conditions. The powders were annealed in quartz tubes with ...

    • Magnetic properties of the Co/Alq(3) interface 

      COEY, JOHN; VENKATESAN, MUNUSWAMY; TOKUC, HUSEYIN; BURKE, FRANKLYN (2011)
      A method is described for measuring the magnetic integrity of ferromagnetic/organic interfaces that involves measuring the magnetic moment per unit area of bilayers with different ferromagnet thicknesses. The method is ...

    • Magnetic study of Fe3O4 nanoparticles incorporated within mesoporous silicon 

      VENKATESAN, MUNUSWAMY (Electrochemical Society, 2010)
      Porous silicon PS matrices with oriented, separated pores grown perpendicular to the surface are used as a template for the incorporation of magnetite nanoparticles. The Fe3O4 particles used for infiltration into the ...

    • Magnetic, magnetotransport, and optical properties of Al-doped Zn0.95Co0.05O thin films 

      VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID (American Institute of Physics, 2007)
      Thin films of 5% Co-doped ZnO with a range of Al codoping exhibit a band-edge shift, which varies with carrier concentration as n2/3. Carrier effective mass is 0.26me and mobility is ~ 10?cm2?V?1?s?1. The doped films, which ...

    • Magnetism in dilute magnetic oxide thin films based on SnO2 

      STAMENOV, PLAMEN; COEY, JOHN; VENKATESAN, MUNUSWAMY (2006)
      Thin films of SnO2 prepared by pulsed-laser deposition on R-cut sapphire substrates exhibit ferromagnetic properties at room temperature when they are doped with Cr, Mn, Fe, Co, or Ni, but not with other 3d cations. ...

    • Magnetism in hafnium dioxide 

      COEY, JOHN; VENKATESAN, MUNUSWAMY (2005)
      Thin films of HfO2 produced by pulsed-laser deposition on sapphire, yttria-stabilized zirconia, or silicon substrates show ferromagnetic magnetization curves with little hysteresis and extrapolated Curie temperatures far ...

    • Magnetism in thin films of CaB6 and SrB6 

      LUNNEY, JAMES GERARD; COEY, JOHN MICHAEL DAVID; LUNNEY, JAMES GERARD; VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID (American Physical Society, 2004)
      Thin films of disordered hexaborides CaB6 and SrB6 deposited by pulsed-laser deposition on MgO (100) or Al2O3 (001) substrates are ferromagnetic. A typical room-temperature moment per unit area of substrate is 350 mB ...

    • Magnetization Process in Dilute Magnetic Oxides 

      COEY, JOHN; VENKATESAN, MUNUSWAMY; STAMENOV, PLAMEN (2010)
      Thin films of dilute magnetic oxides often exhibit high-temperature ferromagnetism with magnetization curves of the form M approximate to M-s tanh(H/H-0); the curves are practically anhysteretic and temperature-independent ...

    • Magnetoresistance of Co-doped ZnO thin films 

      STAMENOV, PLAMEN; COEY, JOHN; VENKATESAN, MUNUSWAMY (2006)
      Longitudinal, transverse, and perpendicular magnetoresistances were investigated at temperatures 1.2 T 300 K in fields of up to 20 T for four ZnO films: one undoped, two with 4% Co one paramagnetic, the other exhibiting ...

    • New two in one magnetic fluorescent nanocomposites 

      VENKATESAN, MUNUSWAMY; GOUNKO, IOURI (SPIE, 2005)
      Magnetite nanoparticles have been coated by a porphyrin derivative to produce new magnetic materials with fluorescent properties. The magnetic nanoparticles were prepared using two different methods, one based on sol-gel ...

    • Optimization of the magnetic properties of nanostructured Y-Co-Fe alloys for permanent magnets 

      COEY, JOHN; VENKATESAN, MUNUSWAMY (2016)
      The structural and magnetic properties of ball-milled Fe-doped YCo 5 − x Fe x ( 0 ≤ x ≤ 0 . 5 ) were investigated. The magnetization increases with Fe-doping up to the solid solubility ...

    • Origin of the Two-Dimensional Electron Gas at LaAlO3=SrTiO3 Interfaces: The Role of Oxygen Vacancies and Electronic Reconstruction 

      COEY, JOHN; VENKATESAN, MUNUSWAMY (2013)
      The relative importance of atomic defects and electron transfer in explaining conductivity at the crystalline LaAlO3=SrTiO3 interface has been a topic of debate. Metallic interfaces with similar electronic properties ...

    • Site-specific order and magnetism in tetragonal Mn3Ga thin films 

      VENKATESAN, MUNUSWAMY; SANVITO, STEFANO (2013)
      Mn 3 Ga bulk material and thin films deposited on several different substrates have been investigated using x-ray and neutron diffraction, x-ray absorption spectroscopy, x-ray magnetic circular dichroism, and ...

    • Site-specific order and magnetism in tetragonal Mn3Ga thin films 

      STAMENOV, PLAMEN; COEY, JOHN; RODE, KARSTEN; SANVITO, STEFANO; VENKATESAN, MUNUSWAMY (2013)
      Mn 3 Ga bulk material and thin films deposited on several different substrates have been investigated using x-ray and neutron diffraction, x-ray absorption spectroscopy, x-ray magnetic circular dichroism, and ...

    • SnO2 doped with Mn, Fe or Co: Room temperature dilute magnetic semiconductors 

      VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID (American Institute of Physics, 2004)
      Room temperature ferromagnetism is found in (Sn1?xMx)O2 (M=Mn, Fe, Co, x=0.05) ceramics where x-ray diffraction confirms the formation of a rutile-structure phase. Room temperature saturation magnetization of 0.2 and 1.8 ...

    • Soft x-ray spectroscopic investigation of ferromagnetic Co-doped ZnO 

      MCGUINNESS, CORMAC; LUNNEY, JAMES; PATTERSON, CHARLES; VENKATESAN, MUNUSWAMY; COEY, JOHN (2006)
      The electronic properties of cobalt-doped ZnO were investigated through site-selective and element-sensitive x-ray-absorption spectroscopy in the vicinity of the Co L2,3 edge, the oxygen K edge, and at the Zn L3 edge. ...

    • Superparamagnetism in MgO-based magnetic tunnel junctions with a thin pinned ferromagnetic electrode 

      COEY, JOHN; FENG, JIA-FENG; VENKATESAN, MUNUSWAMY (2010)
      MgO-based magnetic tunnel junctions have been fabricated with a thin Co40Fe40B20 (CoFeB) layer in the pinned synthetic antiferromagnetic CoFe/Ru/CoFeB stack. An inverted tunneling magnetoresistance is observed due to the ...

    • Tunnel magnetoresistance of disordered low-moment Co2MnSi Heusler alloy films 

      VENKATESAN, MUNUSWAMY; COEY, JOHN MICHAEL DAVID (American Institute of Physics, 2005)
      Thin films of Co(1?x?y)MnxSiy (x = 0.18?0.26 and y = 0.23?0.29) were deposited from elemental targets onto thermal-oxidized Si substrates at room temperature using dc magnetron cosputtering. The as-deposited films appear ...