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Related papers: Impurity-Ion pair induced high-temperature ferroma…

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The nature of the often reported room temperature ferromagnetism in transition metal doped oxides is still a matter of huge debate. Herein we report on room temperature ferromagnetism in high quality Co-doped ZnO (Zn1-xCoxO) bulk samples…

We report room temperature ferromagnetism in boron-doped ZnO both experimentally and theoretically. The single phase Zn1-xBxO films deposited under high oxygen pressure by pulsed-laser deposition show ferromagnetic behavior at room…

Materials Science · Physics 2015-05-18 X. G. Xu , H. L. Yang , Y. Wu , D. L. Zhang , S. Z. Wu , J. Miao , Y. Jiang

The realization of semiconductors that are ferromagnetic above room temperature will potentially lead to a new generation of spintronic devices with revolutionary electrical and optical properties. Transition temperatures in doped ZnO are…

Strongly Correlated Electrons · Physics 2009-11-11 XH Xu , AJ Behan , M Ziese , HJ Blythe , JR Neal , A Mokhtari , MR Ibrahim , AM Fox , GA Gehring

The possibility that the apparent room temperature ferromagnetism, often measured in Co-doped ZnO, is due to uncompensated spins at the surface of wurtzite CoO nanoclusters is investigated by means of a combination of density functional…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 Ruairi Hanafin , Thomas Archer , Stefano Sanvito

Following the theoretical predictions of ferromagnetism in Mn- and Co-doped ZnO, several workers reported ferromagnetism in thin films as well as in bulk samples of these materials. While some observe room-temperature ferromagnetism, others…

Materials Science · Physics 2007-05-23 C. N. R. Rao , F. L. Deepak

The origin of room temperature (RT) ferromagneticlike behavior in ZnO-based diluted magnetic semiconductors is still an unclear topic. The present work concentrates on the appearance of RT magnetic moments in just mixed ZnO/Co3O4 mixtures…

We report room temperature ferromagnetism in as-implanted Eu doped ZnO (ZnO:Eu). To address the origin of ferromagnetism ab initio calculations of ZnO:Eu system are performed. Results show that the ferromagnetism is induced by ZnO point…

Materials Science · Physics 2010-06-22 M. H. N. Assadi , Y. B. Zhang , M. Ionescu , P. Photongkam , S. Li

We report magnetism in carbon doped ZnO. Our first-principles calculations based on density functional theory predicted that carbon substitution for oxygen in ZnO results in a magnetic moment of 1.78 $\mu_B$ per carbon. The theoretical…

Materials Science · Physics 2013-05-29 H. Pan , J. B. Yi , J. Y. Lin , Y. P. Feng , J. Ding , L. H. Van , J. H. Yin

The high temperature ferromagnetism in Sr3YCo4O10+delta perovskite, whose origin has been the subject of a considerable debate, has been studied by neutron powder diffraction and synchrotron X-ray diffraction measurements. Oxygen vacancy…

Magneto-optic studies of ZnO doped with transition metals Co, Mn, V and Ti indicate a significant magnetic circular dichroism (MCD) at the ZnO band edge at room temperature, together with an associated dispersive Faraday rotation. Similar…

Strongly Correlated Electrons · Physics 2009-11-11 JR Neal , AJ Behan , RM Ibrahim , H J Blythe , M Ziese , AM Fox , GA Gehring

Experimental studies of Zn1-xCoxO as thin films or nanocrystals have found ferromagnetism and Curie temperatures above room temperature and that p- or n-type doping of Zn1-xCoxO can change its magnetic state. Bulk Zn1-xCoxO with a low…

Materials Science · Physics 2013-05-29 Charles H. Patterson

The origin of room temperature (RT) ferromagnetism (FM) in Ni doped ZnO samples are systematically investigated through physical, optical, and magnetic properties of nanostructure, prepared by simple low-temperature wet chemical method.…

Co-doped ZnO is the prototypical dilute magnetic oxide showing many of the characteristics of ferromagnetism. The microscopic origin of the long range order however remains elusive, since the conventional mechanisms for the magnetic…

Materials Science · Physics 2015-05-18 Thomas Archer , Chaitanya Das Pemmaraju , Stefano Sanvito

The existence of semiconductors exhibiting long-range ferromagnetic ordering at room temperature still is controversial. One particularly important issue is the presence of secondary magnetic phases such as clusters, segregations, etc...…

Soft x-ray magnetic circular dichroism (XMCD) measurements at the Co L2,3 edges of Co doped rutile TiO2 at room temperature have revealed clear multiplet features characteristic of ferromagnetic Co2+ ions coordinated by O2- ions, being in…

Materials Science · Physics 2007-05-23 K. Mamiya , T. Koide , A. Fujimori , H. Tokano , H. Manaka , A. Tanaka , H. Toyosaki , T. Fukumura , M. Kawasaki

A microscopic explanation for the room temperature ferromagnetism in diluted ZnO:Co is at present rather elusive. Although standard secondary phases can usually be ruled out, it is less clear whether regions with high Co concentration…

Other Condensed Matter · Physics 2008-07-01 Thomas Archer , Ruairi Hanafin , Stefano Sanvito

It is shown that substitution of C or N for O recently proposed as a way to create ferromagnetism in otherwise nonmagnetic oxide insulators is curtailed by formation of impurity pairs, and the resultant C2 spin=1 dimers as well as the…

Materials Science · Physics 2010-12-30 Hua Wu , Alessandro Stroppa , Sung Sakong , Silvia Picozzi , Matthias Scheffler , Peter Kratzer

Using the first-principles density-functional theory plan-wave pseudopotential method, we investigate the structure and magnetism in 25% Mn substitutive and interstitial doped monoclinic, tetragonal and cubic ZrO2 systematically. Our…

Materials Science · Physics 2015-05-13 Xingtao Jia , Wei Yang , Minghui Qin , Jianping Li

We report on the structural and magnetic properties of a cobalt-implanted ZnO film grown on a sapphire substrate. X-ray diffraction and transmission electron microscopy reveal the presence of a (10-10)-oriented hexagonal Co phase in the…

We synthesized pure and Co-doped (6.25 12.5 at.) ZrO$_2$ nanopowders in order to study their magnetic properties.We analyzed magnetic behavior as a function of the amount of Co and the oxygenation, which was controlled by low pressure…

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