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Related papers: Defect-induced ferromagnetism in graphite

200 papers

We report on scanning tunneling microscopy and spectroscopy of grain boundaries in highly oriented pyrolytic graphite. Grain boundaries showed a periodic structure and an enhanced charge density compared to the bare graphite surface. Two…

Materials Science · Physics 2013-05-29 J. Cervenka , C. F. J. Flipse

Room temperature ferromagnetic materials composed only by light elements like carbon, hydrogen and/or nitrogen, so called carbon magnet, are very attractive for creating new material categories both in science and industry. Recently several…

Mesoscale and Nanoscale Physics · Physics 2011-01-24 Norio Ota , Narjes Gorjizadeh , Yoshiyuki Kawazoe

In view of the recent experimental reports of unexpected ferromagnetism in HfO$_{2}$ thin films, we carried out first principles investigations looking for magnetic order possibly brought about by the presence of small concentrations of…

Materials Science · Physics 2007-05-23 Chaitanya Das Pemmaraju , S. Sanvito

Theoretical calculations, based on hybrid exchange density functional theory, are used to show that in graphene a periodic array of defects generates a ferromagnetic ground state at room temperature for unexpectedly large defect…

Materials Science · Physics 2009-11-13 L. Pisani , B. Montanari , N. M. Harrison

Magnetic order emerging in otherwise non-magnetic materials as carbon is a paradigmatic example of a novel type of s-p electron magnetism predicted to be of exceptional high-temperature stability. It has been demonstrated that atomic scale…

We have studied magnetization of graphene nanocrystals obtained by sonic exfoliation of graphite. No ferromagnetism is detected at any temperature down to 2 K. Neither do we find strong paramagnetism expected due to the massive amount of…

Mesoscale and Nanoscale Physics · Physics 2010-11-24 M. Sepioni , R. R. Nair , S. Rablen , J. Narayanan , F. Tuna , R. Winpenny , A. K. Geim , I. V. Grigorieva

This comment addresses several issues in the paper by Sepioni et al., where it is stated that the ferromagnetism in pristine highly oriented pyrolytic graphite (HOPG) reported by several groups in the previous years is most likely due to…

Strongly Correlated Electrons · Physics 2012-06-13 D. Spemann , M. Rothermel , P. Esquinazi , M. Ramos , Y. Kopelevich , H. Ohldag

Information on atomic-scale features is required for a better understanding of the mechanisms leading to magnetism in non-metallic, carbon-based materials. This work reports a direct evaluation of the hyperfine magnetic field produced at…

Void-defect is a possible origin of ferromagnetic feature on pure carbon materials. In our previous paper, void-defect on graphene-nanoribbon show highly polarized spin configuration. In this paper, we studied cases for graphene molecules…

Astrophysics of Galaxies · Physics 2021-07-06 Norio Ota , Aigen Li , Laszlo Nemes , Masaaki Otsuka

The conditions for spontaneous magnetization in a single graphene sheet are discussed in the context of Mermin-Wagner theorem. It is rigorously proved that at any nonzero temperature the graphene monolayer is nonmagnetic as long as its…

Mesoscale and Nanoscale Physics · Physics 2012-11-08 L. Wojtczak

Recent experiments report the existence of ferromagnetic and superconducting fluctuations in graphite at unexpectedly high temperatures. The interplay of disorder and interactions in a 2D graphene layer is shown to give rise to a rich phase…

Strongly Correlated Electrons · Physics 2009-11-10 M. A. H. Vozmediano , F. Guinea , M. P. Lopez-Sancho

This work shows an unconventional route for spin-driven ferroelectricity originating from a metastable magnetic field-induced canting of chromium sublattice in the presence of gadolinium moments in GdCrTiO5 at low temperatures. Compared to…

Strongly Correlated Electrons · Physics 2017-11-29 T. Basu , D. T. Adroja , F. Kolb , H. -A. Krug von Nidda , A. Ruff , M. Hemmida , A. D. Hillier , M. Telling , E. V. Sampathkumaran , A. Loidl , S. Krohns

The defect tolerance nature of organic-inorganic hybrid perovskite is reflected from its stupendous growth in photovoltaic performances. The presence of lattice defect can manipulate or even gives rise to some exceptional properties which…

Motivated by recent studies reporting the formation of localized magnetic moments in doped graphene, we investigate the energetic cost for spin polarizing isolated impurities embedded in this material. When a well-known criterion for the…

Materials Science · Physics 2015-05-14 P. Venezuela , R. B. Muniz , A. T. Costa , D. M. Edwards , S. R. Power , M. S. Ferreira

The existence of high-temperature ferromagnetism in thin films and nanoparticles of oxides containing small quantities of magnetic dopants remains controversial. Some regard these materials as dilute magnetic semiconductors, while others…

Materials Science · Physics 2015-05-18 J. M. D. Coey , P. Stamenov , R. D. Gunning , M. Venkatesan , K. Paul

We discuss different magnetic phenomena observed in carbon-based structures, in particular the diamagnetism, paramagnetism and ferromagnetism observed in graphite, disordered carbon, fullerenes and irradiated carbon structures.

Strongly Correlated Electrons · Physics 2016-08-31 Pablo Esquinazi , Roland Höhne

Using magnetization measurements, we show that point defects in graphene - fluorine adatoms and irradiation defects (vacancies) - carry magnetic moments with spin 1/2. Both types of defects lead to notable paramagnetism but no magnetic…

Mesoscale and Nanoscale Physics · Physics 2012-05-23 R. R. Nair , M. Sepioni , I-Ling Tsai , O. Lehtinen , J. Keinonen , A. V. Krasheninnikov , T. Thomson , A. K. Geim , I. V. Grigorieva

Understanding the magnetic properties of graphenic nanostructures is instrumental in future spintronics applications. These magnetic properties are known to depend crucially on the presence of defects. Here we review our recent theoretical…

Mesoscale and Nanoscale Physics · Physics 2013-04-02 Elton J. G. Santos , Andres Ayuela , Daniel Sanchez-Portal

In the paper we predict a distinctive change of magnetic properties and considerable increase of the Curie temperature caused by the strain fields of grain boundaries in ferromagnetic films. It is shown that a sheet of spontaneous…

Materials Science · Physics 2009-11-07 A. Kadigrobov , Z. Ivanov , R. I. Shekhter , M. Jonson

Defect-induced magnetism in graphene has been predicted theoretically and observed experimentally. However, there are open questions about the origin of the magnetic behavior when substitutional impurities with $sp$ electrons are…

Materials Science · Physics 2022-07-05 J. Hernández-Tecorralco , L. Meza-Montes , M. E. Cifuentes-Quintal , R. de Coss