Browsing by Author "Gardelis, S."

Now showing items 1-13 of 13

    • Article  

      Comparison of free surface polarization of NiMnSb and Co2 MnSi 

      Miyoshi, Y.; Bugoslavsky, Y.; Syed, M. H.; Robinson, T.; Cohen, L. F.; Singh, L. J.; Barber, Z. H.; Grigorescu, C. E. A.; Gardelis, S.; Giapintzakis, John; Roy, W. Van (2006)
      We present a systematic study of the polarization of the transport current from a variety of NiMnSb and Co2 MnSi thin films and bulk material using point contact Andreev reflection spectroscopy. The simple analysis suggests ...
    • Article  

      Indium oxide as a possible tunnel barrier in spintronic devices 

      Androulakis, J.; Gardelis, S.; Giapintzakis, John; Gagaoudakis, E.; Kiriakidis, G. (2005)
      We report the growth of ultra-thin indium oxide layers using the dc-magnetron sputtering method. We demonstrate that good quality tunnel barriers made of indium oxide can be routinely fabricated and employed in spintronic-related ...
    • Article  

      Large positive magnetoresistance in nonstoichiometric NiMnSb thin films on silicon 

      Branford, W. R.; Clowes, S. K.; Syed, M. H.; Bugoslavsky, Y. V.; Gardelis, S.; Androulakis, J.; Giapintzakis, John; Grigorescu, C. E. A.; Berenov, A. V.; Roy, S. B.; Cohen, L. F. (2004)
      The transport properties of pulsed-laser-deposited NiMnSb films on silicon as a function of film thickness were discussed. It was found that a low-temperature upturn was observed in the resistivity for film thicknesses of ...
    • Article  

      Magnetic properties of the half-metallic ferromagnet NiMnSb grown on InSb by pulsed laser deposition 

      Androulakis, J.; Gardelis, S.; Giapintzakis, John; Buckle, P. D. (2004)
      We have grown films of the half-metallic ferromagnet NiMnSb on single crystals of the narrow gap semiconductor InSb by pulsed laser deposition. NiMnSb is a possible candidate for spin injection applications. The film ...
    • Article  

      Magneto-transport properties of NiMnSb thin films on InSb single crystals: Negative giant magnetoresistance 

      Gardelis, S.; Androulakis, J.; Viskadourakis, Z.; Papadopoulou, E. L.; Giapintzakis, John; Rai, S.; Lodha, G. S.; Roy, S. B. (2007)
      In this study we investigated the magneto-transport properties of the ohmic contact between polycrystal-line NiMnSb thin films grown by pulsed laser deposition and n-type degenerate InSb (100) substrates. An unusual negative ...
    • Article  

      Negative giant longitudinal magnetoresistance in NiMnSb InSb: Interface effect 

      Gardelis, S.; Androulakis, J.; Viskadourakis, Z.; Papadopoulou, E. L.; Giapintzakis, John; Rai, S.; Lodha, G. S.; Roy, S. B. (2006)
      We report on the electrical and magnetotransport properties of the contact formed between n -type degenerate InSb (100) substrates and polycrystalline NiMnSb thin films grown using pulsed laser deposition. Negative giant ...
    • Article  

      Possible use of the half-Hausler alloy NiMnSb in spintronics: Synthesis and physical properties of arc melted NiMnSb and of NiMnSb thin films grown on InSb by pulsed laser deposition 

      Gardelis, S.; Androulakis, J.; Monnereau, O.; Buckle, P. D.; Giapintzakis, John (2005)
      We report the growth of single-phase, stoichiometric polycrystalline thin films of the half-Heusler ferromagnet NiMnSb, predicted to be half-metallic, on single crystal (100) InSb substrates heated at 200 °C by pulsed laser ...
    • Article  

      Recent advances in spintronics. Half-metal ferromagnets: Their role in spintronics 

      Gardelis, S.; Androulakis, J.; Migiakis, P.; Giapintzakis, John (2004)
      A review of recent advances in spintronics is presented. We report the structural, magnetic, electrical and thermal properties of the ferromagnetic half-Heusler alloy NiMnSb grown by arcmelting. The bulk material is used ...
    • Article  

      Spin polarisation and anomalous Hall effect in NiMnSb films 

      Branford, W. R.; Roy, S. B.; Clowes, S. K.; Miyoshi, Y.; Bugoslavsky, Y. V.; Gardelis, S.; Giapintzakis, John; Cohen, L. F. (2004)
      NiMnSb has attracted a great deal of interest as a spin injector/detector in spintronic devices because it has a Curie temperature of 728 K and is predicted to be half-metallic (100% spin polarized). NiMnSb has been reported ...
    • Article  

      Structural, magnetic, and electrical properties of NiMnSb thin films grown on InSb by pulsed-laser deposition 

      Gardelis, S.; Androulakis, J.; Giapintzakis, John; Monnereau, O.; Buckle, P. D. (2004)
      We report the growth of single-phase, stoichiometric polycrystalline thin films of the half-Heusler ferromagnet NiMnSb, predicted to be half-metallic, on single crystal InSb (100) substrates heated at 200°C by pulsed laser ...
    • Article  

      Surface and interface study of pulsed-laser-deposited off-stoichiometric NiMnSb thin films on a Si(100) substrate 

      Rai, S.; Tiwari, M. K.; Lodha, G. S.; Modi, M. H.; Chattopadhyay, M. K.; Majumdar, S.; Gardelis, S.; Viskadourakis, Z.; Giapintzakis, John; Nandedkar, R. V.; Roy, S. B.; Chaddah, P. (2006)
      We report a detailed study of surface and interface properties of pulsed-laser-deposited NiMnSb films on a Si(100) substrate as a function of film thickness. As the thickness of films is reduced below 35 nm, formation of ...
    • Article  

      Synthesis and physical properties of arc melted NiMnSb 

      Gardelis, S.; Androulakis, J.; Migiakis, P.; Giapintzakis, John; Clowes, S. K.; Bugoslavsky, Y.; Branford, W. R.; Miyoshi, Y.; Cohen, L. F. (2004)
      The synthesis and physical properties of arc melted NiMnSb were studied using X-ray diffraction analysis. It was observed that the half metallicity in NiMnSb is supported by the integer saturation magnetization value at 5 ...
    • Article  

      Thickness dependence of Hall transport in Ni1.15Mn 0.85Sb thin films on silicon 

      Branford, W. R.; Clowes, S. K.; Bugoslavsky, Y. V.; Gardelis, S.; Androulakis, J.; Giapintzakis, John; Grigorescu, C. E. A.; Manea, S. A.; Freitas, R. S.; Roy, S. B.; Cohen, L. F. (2004)
      Highly spin polarized Heusler alloys, NiMnSb and Co2MnSi, attract a great deal of interest as potential spin injectors for spintronic applications. Spintronic devices require control of interfacial properties at the ...