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- 1. Angew. Chem. Int. Ed. 47, (2008) , Wily , “Ag@AgCl: A Highly Efficient and Stable Photocatalyst Active under Visible Light”, PengWang, Baibiao Huang,* Xiaoyan Qin, Xiaoyang Zhang, Ying Dai, JiyongWei, and Myung-Hwan Whangbo
- 2. J.Am.Chem.Soc. 130, 48 (2008) , ACS , “Enhanced Ferromagnetism and Tunable Saturation Magnetization of Mn/C Codoped GaN Nanostructures Synthesized by Carbothermal Nitridation”, Zeyan Wang, Baibiao Huang, Lin Yu, Ying Dai, Peng Wang, Xiaoyan Qin, Xiaoyang Zhang, Jiyong Wei, Jie Zhan, Xiangyang Jing, Haixia Liu, and Myung-Hwan WhangboMn/C-codoped GaN nanostructures were synthesized by carbothermal nitridation with active charcoal as the carbon source. Nanostructures such as zigzag nanowires and nanoscrews were observed by varying the reaction time and the C/Ga molar ratio of the starting material used for the synthesis. The structures and morphologies of the as-grown samples were characterized by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy measurements. The doping of both Mn and C in the GaN matrix was confirmed by X-ray photoelectron spectroscopy measurements, and the ferromagnetic properties of Mn/C-codoped GaN samples were confirmed by room-temperature magnetization measurements. The saturation magnetization of Mn/C-codoped GaN increases steadily with increasing C/Ga molar ratio of the starting material at a rate of ~0.023 emu/g per C/Ga molar ratio, and the ferromagnetism of Mn/C-codoped GaN can be stronger than that of Mn-doped GaN by a factor of ~40. A plausible growth mechanism was proposed, and the role of carbon codoping in tuning the morphology and ferromagnetic property was discussed. Our work suggests that carbon doping in the GaN matrix favors the N sites over the Ga sites, Mn/C-codoping in the GaN matrix is energetically favorable, and the C-codoping strongly enhances the preference of the FM coupling to the AFM coupling between the two doped Mn sites. These suggestions were probed on the basis of first-principles density functional theory electronic structure calculations for a number of model doped structures constructed with a 32-atom 2 × 2 × 2 supercell. (Read more)
- 3. J. Appl. Phys. 102, 103514 (2007) , AIP , “Characterization of defects in ZnO nanocrystals: Photoluminescence and positron annihilation spectroscopic studies”, A. K. Mishra, S. K. Chaudhuri, S. Mukherjee, A. Priyam, A. Saha, and D. DasDefects present in ZnO nanocrystals prepared by a wet chemical method have been characterized by photoluminescence (PL) and positron annihilation spectroscopy (PAS) techniques. The as-prepared sample was heat treated at different temperatures to obtain nanocrystals in the size range of 19–39 ... (Read more)
- 4. Phys. Rev. B 75, 195215 (2007) , “Effect of Co and O defects on the magnetism in Co-doped ZnO: Experiment and theory”, G. S. Chang, E. Z. Kurmaev, D. W. Boukhvalov, L. D. Finkelstein, S. Colis, T. M. Pedersen, A. Moewes, and A. DiniaThe electronic structure of Zn1−xCoxO (x=0.02, 0.06, and 0.10) diluted magnetic semiconductors is investigated using soft x-ray emission spectroscopy and first-principles calculations. X-ray absorption and emission measurements reveal that most Co... (Read more)
- 5. Phys. Rev. B 75, 144404 (2007) , “Ferromagnetism in Fe-doped ZnO nanocrystals: Experiment and theory”, Debjani Karmakar, S. K. Mandal, R. M. Kadam, P. L. Paulose, A. K. Rajarajan, T. K. Nath, A. K. Das, I. Dasgupta, and G. P. DasFe-doped ZnO nanocrystals are successfully synthesized and structurally characterized by using x-ray diffraction and transmission electron microscopy. Magnetization measurements on the same system reveal a ferromagnetic to paramagnetic transition temperature above 450 K with a low-temperature... (Read more)
- 6. Phys. Rev. B 75, 113201 (2007) , “Local structure around Mn atoms in Si crystals implanted with Mn+ studied using x-ray absorption spectroscopy techniques”, A. Wolska, K. Lawniczak-Jablonska, M. Klepka, M. S. Walczak, and A. MisiukThe local order around Mn atoms in the Mn-implanted Si samples, with ferromagnetic properties, has been investigated by use of x-ray-absorption spectroscopy techniques. Analysis of both extended x-ray-absorption fine structure and x-ray absorption near-edge structure spectra clearly indicates that... (Read more)
- 7. Phys. Rev. B 75, 085203 (2007) , “Structural and magnetic properties of Mn-implanted Si”, Shengqiang Zhou, K. Potzger, Gufei Zhang, A. Mücklich, F. Eichhorn, N. Schell, R. Grötzschel, B. Schmidt, W. Skorupa, M. Helm, J. Fassbender, and D. GeigerStructural and magnetic properties in Mn-implanted, p-type Si were investigated. High resolution structural analysis techniques such as synchrotron x-ray diffraction revealed the formation of MnSi1.7 nanoparticles already in the as-implanted samples. Depending on the Mn fluence,... (Read more)
- 8. phys. stat. sol. (b) 244, 279 (2007) , Wiley InterScience , “High-pressure X-ray diffraction study of ternary and non-stoichiometric PbTe and PbSe crystals”, S.V. Ovsyannikov, V.V. Shchennikov, A.Y. Manakov, A.Y. Likhacheva, I.F. Berger, A.I. Ancharov, M.A. SheromovThe paper reports the pressure-induced phase transitions observed in ternary PbTe and PbSe compounds (Pb1-x Snx Te, Pb1-x Mnx Te, Pb1-x Snx Se) and non-stoichiometric PbTe ones... (Read more)
- 9. Appl. Phys. Lett. 89, 042503 (2006) , “Evidence for magnetism due to oxygen vacancies in Fe-doped HfO2 thin films”, Nguyen Hoa Hong, Nathalie Poirot, and Joe SakaiFe-doped HfO2 thin films are room temperature ferromagnetic. In comparison with results of the undoped HfO2 films, it seems that the Fe doping is not the main cause for the ferromagnetism but only acts as a catalyst. Experimental results of oxygen annealing and vacuum heat... (Read more)
- 10. Appl. Phys. Lett. 88, 224102 (2006) , “Imaging defects in strained-silicon thin films by glancing-incidence x-ray topography”, D. R. Black, J. C. Woicik, M. Erdtmann, T. A. LangdoX-ray topographical images from thin (50 nm) strained-Si films grown on relaxed, planarized crystalline SiGe-on-Si (001) virtual substrates have been imaged by glancing-incidence monochromatic x-ray topography. This extremely asymmetric diffraction geometry, utilizing (311) diffraction planes, can... (Read more)
- 11. J. Appl. Phys. 100, 023512 (2006) , “Stacking faults and twin boundaries in fcc crystals determined by x-ray diffraction profile analysis”, Levente Balogh, Gábor Ribárik, and Tamás UngárA systematic procedure is developed to evaluate the density of planar defects together with dislocations and crystallite or subgrain size by x-ray line profile analysis in fcc crystals. Powder diffraction patterns are numerically calculated by using the DIFFAX software for intrinsic and extrinsic... (Read more)
- 12. J. Appl. Phys. 99, 113507 (2006) , “Grazing incidence small-angle x-ray scattering from defects induced by helium implantation in silicon”, D. Babonneau, M.-F. Beaufort, A. Declémy, J.-F. Barbot, and J.-P. SimonThe formation and growth of defects, including nanocavities and extended interstitial-type defects, created by helium implantation in silicon (50 keV, 7.1015 cm2) in the temperature range of 100550 °C has been investigated by grazing incidence small-angle... (Read more)
- 13. J. Appl. Phys. 99, 104906 (2006) , “An x-ray topographic study of diamond anvils: Correlation between defects and helium diffusion”, Agnès Dewaele, Paul Loubeyre, and Ramesh AndréX-ray topographic images of several dozens of diamonds have been recorded before and after their use as anvils in a diamond anvil high pressure cell. The aim of this study is to better understand and prevent the breakage of diamond anvils when they are used in contact with a helium sample. Indeed,... (Read more)
- 14. J. Appl. Phys. 99, 103509 (2006) , “X-ray scattering study of hydrogen implantation in silicon”, Nicolas Sousbie, Luciana Capello, Joël Eymery, François Rieutord, and Chrystelle LagaheThe effect of hydrogen implantation in silicon single crystals is studied using high-resolution x-ray scattering. Large strains normal to the sample surface are evidenced after implantation. A simple and direct procedure to extract the strain profile from the scattering data is described. A... (Read more)
- 15. J. Appl. Phys. 99, 043509 (2006) , “Influence of metal trapping on the shape of cavities induced by high energy He+ implantation”, R. El Bouayadi, G. Regula, M. Lancin, B. Pichaud, and M. DesvignesIn He implantation induced cavities highly contaminated with metals (Au, Ni, Pt) we found that, when no three-dimensional structure is observed, the shape of the cavities can be strongly modified depending on the nature of the metal and on its trapped quantity. The equilibrium shape of cavities is... (Read more)
- 16. J. Appl. Phys. 99, 011101 (2006) , “Degradation of hexagonal silicon-carbide-based bipolar devices”, M. Skowronski and S. HaOnly a few years ago, an account of degradation of silicon carbide high-voltage p-i-n diodes was presented at the European Conference on Silicon Carbide and Related Compounds (Kloster Banz, Germany, 2000). This report was followed by the intense effort of multiple groups... (Read more)
- 17. Mater. Sci. Eng. B 126, 222-225 (2006) , “Magnetic properties of a new spintronic material—GaN:Fe”, H. Przybylińska, A. Wolos, M. Kiecana, M. Sawicki, T. Dietl, H. Malissa, C. Simbrunner, M. Wegscheider, H. Sitter, K. Rumpf, P. Granitzer, H. Krenn and W. JantschWe report on metal-organic chemical vapour deposition growth of GaN:Fe and its characterization by means of high-resolution X-ray diffraction, secondary ion mass spectroscopy, electron spin resonance, and magnetization measurements. Electron spin resonance studies demonstrate the existence of Fe in... (Read more)
- 18. Phys. Rev. B 74, 245205 (2006) , “Mn incorporation in as-grown and annealed (Ga,Mn)As layers studied by x-ray diffraction and standing-wave fluorescence”, V. Holý, Z. Matj, O. Pacherová, V. Novák, M. Cukr, K. Olejník, and T. JungwirthA combination of high-resolution x-ray diffraction and a technique of x-ray standing-wave fluorescence at grazing incidence is employed to study the structure of a (Ga,Mn)As-diluted magnetic semiconductor and its changes during post-growth annealing steps. We find that the film is formed by a... (Read more)
- 19. Phys. Rev. B 74, 235213 (2006) , “Mn 3d electronic configurations in (Ga1−xMnx)As ferromagnetic semiconductors and their influence on magnetic ordering”, F. Kronast, R. Ovsyannikov, A. Vollmer, H. A. Dürr, W. Eberhardt, P. Imperia, D. Schmitz, G. M. Schott, C. Ruester, C. Gould, G. Schmidt, K. Brunner, M. Sawicki, and L. W. MolenkampWe applied x-ray absorption spectroscopy and x-ray magnetic circular dichroism (XMCD) at the Mn 2p-3d resonances to study the Mn 3d electronic configuration and the coupling of Mn 3d magnetic moments in various Ga1−xMnxAs films.... (Read more)
- 20. Phys. Rev. B 74, 205428 (2006) , “Er site in Er-implanted Si nanoclusters embedded in SiO2”, C. Maurizio, F. Iacona, F. D'Acapito, G. Franzò, and F. PrioloWe have investigated by extended x-ray absorption fine structure spectroscopy the local order around Er atoms introduced by ion implantation in substoichiometric silica films prepared by plasma enhanced chemical vapor deposition, where Si nanoclusters have been formed by different preimplantation... (Read more)
- 21. Phys. Rev. B 74, 140502(R) (2006) , “Lattice parameters and thermal expansion of superconducting boron-doped diamonds”, V. V. Brazhkin, E. A. Ekimov, A. G. Lyapin, S. V. Popova, A. V. Rakhmanina, S. M. Stishov, V. M. Lebedev, Y. Katayama, and K. KatoUsing two different high-pressure techniques, we have prepared boron-doped diamonds with atomic concentration of the dopant ranging from 0.04% to 4% (from 7×1019 to 7×1021 atom/cm3) and studied the lattice constants and thermal expansion of the diamonds... (Read more)
- 22. Thin Solid Films 496, 169-173 (2006) , “Green luminescence from Mn ions in ZnO–GeO2 glasses prepared by sol–gel method and their glass ceramics”, Tomoe Sanada, Kazuhiro Yamamoto, Noriyuki Wada , Kazuo KojimaZn2SiO4:Mn2+ is one of the green light luminants used for cathode ray tubes of televisions. Recently, optical materials emitting strong visible light under lower energy excitation have been expected. To obtain new luminants of high quality, we prepared Mn ion doped ZnO–GeO2 glasses and glass... (Read more)
- 23. Chem. Phys. Lett. 415, 337 (2005) , “No ferromagnetism in Mn doped ZnO semiconductors”, J. Alaria, P. Turek, M. Bernard, M. Bouloudenine, A. Berbadj, N. Brihi, G. Schmerber, S. Colis , A. DiniaPolycrystalline Zn1 − xMnxO was synthesized by co-precipitation method with xvarying between 0.01 and 0.10. Although X-ray diffraction patterns show a typical würtzite structure with no additional peaks for all samples, Raman spectroscopy indicates the appearance of an additional mode in... (Read more)
- 24. J. Magn. Magn. Mater. 302, 118 (2005) , “Magnetism origin of Mn-doped ZnO nanoclusters”, J.H. Li, D.Z. Shen, J.Y. Zhang, D.X. Zhao, B.S. Li, Y.M. Lu, Y.C. Liu , X.W. FanZnMnO nanoclusters were synthesized by the sol–gel method. The structural and magnetic characters were investigated. The XRD spectrum shows ZnMnO nanoclusters are hexagonal wurtzite structures and a small quantity of ZnMn2O4 phase is also present in the spectrum. The percentages of Zn and Mn... (Read more)
- 25. Mater. Sci. Eng. C 25, 614-617 (2005) , “Incorporation of cobalt into ZnO nanoclusters”, Igor Ozerov, Françoise Chabre and Wladimir MarineThe structural, optical and magnetic properties of nanostructured ZnO films co-doped with cobalt and aluminium have been studied. The nanocrystalline films, with cluster sizes in range 50–100 nm, were deposited by pulsed laser ablation in a mixed atmosphere of oxygen and helium. The... (Read more)
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