Journal ArticleDOI
Oxygen vacancy controlled tunable magnetic and electrical transport properties of (Li, Ni)-codoped ZnO thin films
TLDR
In this article, the electrical, magnetic, and magnetotransport properties of Li-Ni codoped ZnO thin films in the electron dominated, hole dominated, and insulating regimes were investigated.Abstract:
We investigated the electrical, magnetic, and magnetotransport properties of Li–Ni codoped ZnO thin films in the electron dominated, hole dominated, and insulating regimes. In a narrow window of oxygen growth pressure, 10−3–10−2 mbar, the films exhibited p-type conductivity with a maximum hole concentration ∼8.2×1017 cm−3. Magnetoresistance exhibited by the films is attributed to scattering of charge carriers due to localized magnetic moments. Insulating films showed superparamagnetic behavior, whereas both n-type and p-type films showed room temperature ferromagnetism. Our findings suggest that oxygen vacancies and Ni ions in cation site are jointly responsible for ferromagnetism that is not dependent on the carrier type.read more
Citations
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Journal ArticleDOI
Effect of Ist group elements codoping on structural, optical and magnetic properties of ZnO:Co nanoparticles
TL;DR: In this article, the structural properties of the prepared samples were investigated by X-ray diffraction pattern, Xray photoelectron spectroscopy, scanning electron microscope and Raman spectra measurements.
Journal ArticleDOI
Structural and ferromagnetic properties of Sn0.95-x(Mn0.05,Lix)O2
TL;DR: Li ions can effectively mediate the density of carriers in Sn 0.95 Mn 0.05 O 2, further enhancing the magnetic moment at low temperature, reaching its maximum of M s ǫ = 1.06 μ B /Mn when xǫ= 0.06 as mentioned in this paper.
Journal ArticleDOI
High responsivity n-ZnO nanorods/p-GaN heterojunction-based UV-A photodetectors
Bellarmine Francis,Reethu Sebastian,Tejendra Dixit,Kolla Lakshmi Ganapathi,M. S. Ramachandra Rao +4 more
TL;DR: In this paper , the fabrication of ZnO/p-GaN based high responsivity ultraviolet (UV) photodetector was reported, where two different types of precursors (nitrate and chloride) were used for the growth of nanorods.
Book ChapterDOI
Effect of Oxygen Pressure on Photoluminescence Spectra and Hall Coefficients of Li–Ni Co-Doped ZnO Films Grown by a Pulsed Laser Deposition
Kentaro Sakai,K. Ishikura,Daisuke Ohori,D. Nakamura,Atsuhiko Fukuyama,Tatsuo Okada,M. S. Ramachandra Rao,Tetsuo Ikari +7 more
TL;DR: In this paper, the effect of the oxygen gas pressure on the physical properties of p-type ZnO films was investigated through Hall and photoluminescence (PL) measurements, and the acceptor level was indeed formed by the co-doping of Li and Ni impurities.
Book ChapterDOI
Control of ZnO Nano-Crystals Synthesized by Nanoparticle-Assisted Pulsed Laser Deposition Using Buffer Layer and Laser Irradiation
Daisuke Nakamura,Tetsuya Shimogaki,Kota Okazaki,I. A. Palani,Mitsuhiro Higashihata,Tatsuo Okada +5 more
TL;DR: In this paper, the growth density and position of the ZnO nano crystals with a buffer layer and a buffer patterned by interference laser irradiation, respectively, were controlled.
References
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Donor impurity band exchange in dilute ferromagnetic oxides.
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Journal ArticleDOI
Repeated temperature modulation epitaxy for p-type doping and light-emitting diode based on ZnO
Atsushi Tsukazaki,Akira Ohtomo,Takeyoshi Onuma,M. Ohtani,Takayuki Makino,Masatomo Sumiya,Keita Ohtani,Shigefusa F. Chichibu,S. Fuke,Yusaburou Segawa,Hideo Ohno,Hideomi Koinuma,Masashi Kawasaki +12 more
TL;DR: In this paper, the authors used a new technique to fabricate p-type ZnO reproducibly, and showed high-quality undoped films with electron mobility exceeding that in the bulk.
Journal ArticleDOI
Thin films: unexpected magnetism in a dielectric oxide.
TL;DR: It is shown that thin films of hafnium dioxide (HfO2), an insulating oxide better known as a dielectric layer for nanoscale electronic devices, can be ferromagnetic even without doping.
Journal ArticleDOI
Anisotropic ferromagnetism in substituted zinc oxide.
TL;DR: Results are interpreted in terms of a spin-split donor impurity-band model, which can account for ferromagnetism in insulating or conducting high-k oxides with concentrations of magnetic ions that lie far below the percolation threshold.