Browsing by Subject "Polycrystalline materials"

Now showing items 1-13 of 13

    • Article  

      Ellipsometric analysis of ion-implanted polycrystalline silicon films before and after annealing 

      Lioudakis, Emmanouil E.; Nassiopoulou, Androula Galiouna; Othonos, Andreas S. (2006)
      A study of arsenic ion-implanted polycrystalline silicon films before and after annealing at various temperatures has been performed using spectroscopic ellipsometry in the ultraviolet to the visible spectral region. Using ...
    • Article  

      Femtosecond carrier dynamics in implanted and highly annealed polycrystalline silicon 

      Lioudakis, Emmanouil E.; Nassiopoulou, Androula Galiouna; Othonos, Andreas S. (2006)
      We have studied the ultrafast optical response of highly implanted and highly annealed polycrystalline silicon films using 400 nm ultrashort amplified pulses with fluence ranging between 8 mJ cm-2 to 56 mJ cm -2. Transient ...
    • Article  

      Growth of polycrystalline LaNi 1-xCo xO 3 (x = 0.3, 0.5) thin films on Si(100) by pulsed laser deposition 

      Androulakis, J.; Klini, A.; Manousaki, A.; Violakis, G.; Giapintzakis, John (2004)
      Polycrystalline LaNi 1_xCo xO 3 (x = 0.5, 0.3) thin films have been deposited on polished Si(lOO) substrates by pulsed laser deposition. The films are grown at 650°C in ambient oxygen pressure of 0.4 mbar with an incident ...
    • Conference Object  

      Initial assessment of the thermoelectric properties for the mixed system K2-xRbxBi8Se13 

      Ireland, J. R.; Kyratsi, Theodora; Kanatzidis, M. G.; Kannewurf, C. R. (Affiliation: Dept. of Elec. and Comp. Engineering, Northwestern University, Evanston, IL 60208-3118, United StatesCorrespondence Address: Ireland, J.R.Dept. of Elec. and Comp. Engineering, Northwestern University, Evanston, IL 60208-3118, United States, 2002)
      In previous studies we have investigated the thermoelectric properties of undoped and doped compositions of β-K2Bi8Se13. The attempt to substitute Rb for K resulted in a different structure type, but with potentially useful ...
    • Article  

      La0.95Sr0.05Coo3: An efficient room-temperature thermoelectric oxide 

      Andrbulakis, J.; Migiakis, P.; Giapintzakis, John (2004)
      Electric resistivity, thermal conductivity, and the thermopower of polycrystalline Sr-doped LaCoO3 with composition La 0.9Sr0.5CoO3 were measured. The crystal structure of the synthesized powders was determined by x-ray ...
    • Article  

      LaSrMnCoO6: A new cubic double perovskite oxide 

      Androulakis, J.; Katsarakis, N.; Giapintzakis, John; Vouroutzis, N.; Pavlidou, E.; Chrissafis, K.; Polychroniadis, E. K.; Perdikatsis, V. (2003)
      Single-phase polycrystalline powder samples of the double perovskite oxide LaSrMnCoO6 were synthesized by the Pechini (citrate-gel) technique. The structural, magnetic and electrical properties of the obtained powders were ...
    • Article  

      Normal and defective perylene substitution sites in alkane crystals 

      Leontidis, Epameinondas; Heinz, H.; Palewska, K.; Wallenborn, E. -U; Suter, U. W. (2001)
      The substitution nature of perylene in polycrystalline solid alkane matrices was examined. Low temperature excitation-emission matrix spectroscopy was used to determine substitution sites in alkane matrices from hexane to ...
    • Article  

      Probing carrier dynamics in implanted and annealed polycrystalline silicon thin films using white light 

      Lioudakis, Emmanouil E.; Othonos, Andreas S.; Nassiopoulou, Androula Galiouna (2006)
      Polycrystalline silicon thin film samples implanted and annealed at various temperatures have been studied using ultrafast laser pulse excitation. Nondegenerate pump-probe technique has been utilized to investigate carrier ...
    • Article  

      Realization of La2MnVO6: Search for half-metallic antiferromagnetism? 

      Androulakis, J.; Katsarakis, N.; Giapintzakis, John (2002)
      Single-phase polycrystalline La2MnVO6 samples were synthesized by arc-melting and characterized by X-ray diffraction, magnetization and resistivity measurements. We find that the compound has cubic (space group Fm3̄m), ...
    • Conference Object  

      Stoichiometry issues in pulsed laser deposition of the ferromagnetic alloy NiMnSb 

      Grigorescu, C. E. A.; Monnereau, O.; Manea, S. A.; Notonier, R.; Klini, A.; Zorba, V.; Manousaki, A.; Giapintzakis, John; Fotakis, C. (Affiliation: NIRDO, BucharestAffiliation: MADIREL, Univ. Provence Centre St. Charles, Marseille, FranceAffiliation: Natl. Inst. Res. Devmt. Mat. Phy., BucharestAffiliation: Foundation for Res. and Technology, HELLAS, Inst. Electron. Structure and Laser, Heraklion, Crete, GreeceCorrespondence Address: Grigorescu, C.E.A.NIRDO, Bucharest, 2002)
      We report on the reproducible growth of stoichiometric thin films of ferromagnetic intermetallic compound NiMnSb by pulsed laser deposition (PLD) on various substrates. The films are grown at moderate temperature (around ...
    • 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  

      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 ...
    • Conference Object  

      Transport properties of the doped thermoelectric material K2Bi8-xSbxSe13 

      Brazis, P. W.; Ireland, J. R.; Lane, M. A.; Kyratsi, Theodora; Chung, D. Y.; Kanatzidis, M. G.; Kannewurf, C. R. (Affiliation: Dept. of Electrical and Comp. Eng., Northwestern University, Evanston, IL 60208-3118, United StatesCorrespondence Address: Brazis, P.W.Dept. of Electrical and Comp. Eng., Northwestern University, Evanston, IL 60208-3118, United States, 2001)
      The synthesis, physicochemical, spectroscopic, and structural characterization of the compound β-K2Bi8Se13 has been previously reported. The results indicated that this material should be investigated further for possible ...