English
Related papers

Related papers: Irradiation Enhanced paramagnetism on graphene nan…

200 papers

This article is a continuation of our previous studies of the frictional anisotropy of metal nanoparticles on the surface of a graphene substrate for other temperature conditions. The friction force acting on palladium nanoparticles on a…

Mesoscale and Nanoscale Physics · Physics 2021-03-30 A. V. Khomenko , M. V. Zakharov

By combining classical molecular dynamics simulations and density functional theory total energy calculations, we study the possibility of doping graphene with B/N atoms using low-energy ion irradiation. Our simulations show that the…

Materials Science · Physics 2015-03-18 E. H. Åhlgren , J. Kotakoski , A. V. Krasheninnikov

We demonstrate a large enhancement of the spin accumulation in monolayer graphene following electron-beam induced deposition of an amorphous carbon layer at the ferromagnet-graphene interface. The enhancement is 10^4-fold when graphene is…

Mesoscale and Nanoscale Physics · Physics 2015-06-24 I. Neumann , M. V. Costache , G. Bridoux , J. F. Sierra , S. O. Valenzuela

As impermeable to gas molecules and at the same time transparent to high-energy ions, graphene has been suggested as a window material for separating a high-vacuum ion beam system from targets kept at ambient conditions. However,…

Materials Science · Physics 2014-04-30 E. H. Åhlgren , J. Kotakoski , O. Lehtinen , A. V. Krasheninnikov

Ion irradiation of semiconductors is a well understood method to tune the carrier concentration in a controlled manner. We show that the ferromagnetism in GaMnAs films, known to be hole-mediated, can be modified by He ion irradiation. The…

(MnNiSi)1-(Fe2Ge)x composition (x=0.34) alloy was prepared by arc melting, crushed, and sieved to approximately <32 microns. They were utilized in examining the possible magnetic and structural changes when exposed to a dosage of a…

Materials Science · Physics 2023-03-16 John Peter J. Nunez , Vaibhav Sharma , Jessika V. Rojas , Radhika Barua , Ravi L. Hadimani

Two-dimensional (2D) magnets are of significant interest both as a platform for exploring novel fundamental physics and for their potential in spintronic and optoelectronic devices. Recent bulk magnetometry studies have indicated a weak…

Graphene nanoribbons (GNRs) are atomically precise stripes of graphene with tunable electronic properties, making them promising for room-temperature switching applications like field-effect transistors (FETs). However, challenges persist…

We provide evidence for a finite temperature ferromagnetic transition in 2-dimensions as $H \to 0$ in thin films of $^3$He on graphite, a model system for the study of two-dimensional magnetism. We perform pulsed and CW NMR experiments at…

Condensed Matter · Physics 2009-11-07 H. M. Bozler , Yuan Gu , Jinshan Zhang , K. S. White , C. M. Gould

Si nanopillars of less than 50 nm diameter have been irradiated in a helium ion microscope with a focused Ne$^+$ beam. The morphological changes due to ion beam irradiation at room temperature and elevated temperatures have been studied…

Room-temperature ferromagnetism is observed in (110) oriented ZnO films containing 5 at % of Sc, Ti, V, Fe, Co or Ni, but not Cr, Mn or Cu ions. There are large moments, 1.9 and 0.5 muB/atom for Co- and Ti-substituted oxides, respectively.…

Materials Science · Physics 2009-11-10 M. Venkatesan , C. B. Fitzgerald , J. G. Lunney , J. M. D. Coey

The optical excitations of elongated graphene nanoflakes of finite length are investigated theoretically through quantum chemistry semi-empirical approaches. The spectra and the resulting dipole fields are analyzed, accounting in full…

We have investigated the variation in the magnetization of highly ordered pyrolytic graphite (HOPG) after neutron irradiation, which introduces defects in the bulk sample and consequently gives rise to a large magnetic signal. We observe…

Nanographite systems, where graphene sheets of the orders of the nanometer size are stacked, show novel magnetic properties, such as, spin-glass like behaviors, and the change of ESR line widths while gas adsorptions. Recently, it has been…

Soft Condensed Matter · Physics 2016-08-31 Kikuo Harigaya , Naoki Kawatsu , Toshiaki Enoki

We report on the magnetic properties of monovacancy defects in neutron-irradiated graphite, probed by $^{13}$C nuclear magnetic resonance spectroscopy. The bulk paramagnetism of the defect moments is revealed by the temperature dependence…

Materials Science · Physics 2017-12-21 Z. T. Zhang , C. Xu , D. Dmytriieva , S. Molatta , J. Wosnitza , Y. T. Wang , M. Helm , Shengqiang Zhou , H. Kühne

Nanocomposites comprised of insulated magnetic single-domain particles are promising candidates for high-frequency, eddy current free, soft magnetic materials, but tend to suffer from low magnetic susceptibility ($<20$). Particle alignment…

A distant-neighbor quantum-mechanical method is used to study the nonlinear optical wave mixing in graphene nanoflakes (GNFs), including sum- and difference-frequency generation, as well as four-wave mixing. Our analysis shows that…

Optics · Physics 2022-03-11 Hanying Deng , Changming Huang , Yingji He , Fangwei Ye

The magnetic moment and magnetization in GaAs/Ga$_{0.84}$In$_{0.16}$As/GaAs heterostructures with Mn deluted in GaAs cover layers and with atomically controlled Mn $\delta$-layer thicknesses near GaInAs-quantum well ($\sim$3 nm) in…

Materials Science · Physics 2015-06-22 T. Charikova , V. Okulov , A. Gubkin , A. Lugovikh , K. Moiseev , V. Nevedomsky , Yu. Kudriavstev , S. Gallardo , M. Lopez

Molecular dynamics (MD) simulations were performed to study the formation process of nanopores in a suspended graphene sheet irradiated by using energetic ions though a mask. By controlling the ion parameters including mass, energy and…

Mesoscale and Nanoscale Physics · Physics 2016-03-10 Weisen Li , Li Liang , Shijun Zhao , Shuo zhang , Jianming Xue

Ferromagnetic InMnAs has been prepared by Mn ion implantation and pulsed laser annealing. The InMnAs layer reveals a saturated magnetization of 2.6 mu_B/Mn at 5 K and a perpendicular magnetic anisotropy. The Curie temperature is determined…

Materials Science · Physics 2012-09-27 Shengqiang Zhou , Yutian Wang , Zenan Jiang , Eugen Weschke , Manfred Helm