English
Related papers

Related papers: Probing charged impurities in suspended graphene u…

200 papers

We study charged impurity scattering and static screening in a top-gated substrate-supported graphene nanostructure. Our model describes how boundary conditions can be incorporated into scattering, sheds light on the dielectric response of…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Zhun-Yong Ong , Massimo V. Fischetti

Raman Spectroscopy is able to probe disorder in graphene through defect-activated peaks. It is of great interest to link these features to the nature of disorder. Here we present a detailed analysis of the Raman spectra of graphene…

Mesoscale and Nanoscale Physics · Physics 2012-07-10 Axel Eckmann , Alexandre Felten , Artem Mishchenko , Liam Britnell , Ralph Krupke , Kostya S. Novoselov , Cinzia Casiraghi

Since the experimental realization of graphene1, extensive theoretical work has focused on short-range disorder2-5, ''ripples''6, 7, or charged impurities2, 3, 8-13 to explain the conductivity as a function of carrier density…

Other Condensed Matter · Physics 2009-11-13 J. H. Chen , C. Jang , M. S. Fuhrer , E. D. Williams , M. Ishigami

Raman spectroscopic studies of graphene have attracted much interest. The G-band Raman intensity of a single layer graphene on Si substrate with 300 nm SiO2 capping layer is surprisingly strong and is comparable to that of bulk graphite. To…

Materials Science · Physics 2009-11-13 Yingying Wang , Zhenhua Ni , Zexiang Shen , Haomin Wang , Yihong Wu

Raman spectroscopy, a fast and nondestructive imaging method, can be used to monitor the doping level in graphene devices. We fabricated chemical vapor deposition (CVD) grown graphene on atomically flat hexagonal boron nitride (hBN) flakes…

Materials Science · Physics 2013-12-09 Kanokporn Chattrakun , Shengqiang Huang , K. Watanabe , T. Taniguchi , A. Sandhu , B. J. LeRoy

We present a Raman study of Ar(+)-bombarded graphene samples with increasing ion doses. This allows us to have a controlled, increasing, amount of defects. We find that the ratio between the D and G peak intensities for a given defect…

We analyze the scattering sector of the Hamiltonians for both gapless and gapped graphene in the presence of a charge impurity using the 2D Dirac equation, which is applicable in the long wavelength limit. We show that for certain range of…

Mesoscale and Nanoscale Physics · Physics 2011-04-07 Kumar S. Gupta , Andjelo Samsarov , Siddhartha Sen

Avoiding charge density fluctuations and impurities in graphene is vital for high-quality graphene-based devices. Traditional characterization methods require device fabrication and electrical transport measurements, which are…

Applied Physics · Physics 2019-08-30 Zhuofa Chen , Nathan Ullberg , Mounika Vutukuru , David Barton , Anna K Swan

We calculate the carrier density dependent ground state properties of graphene in the presence of random charged impurities in the substrate taking into account disorder and interaction effects non-perturbatively on an equal footing in a…

Mesoscale and Nanoscale Physics · Physics 2008-10-17 Enrico Rossi , S. Das Sarma

We report strong variations in the Raman spectra for different single-layer graphene samples obtained by micromechanical cleavage, which reveals the presence of excess charges, even in the absence of intentional doping. Doping…

Materials Science · Physics 2008-01-07 C. Casiraghi , S. Pisana , K. S. Novoselov , A. K. Geim , A. C. Ferrari

The influence of GaN nanowires on the optical and electrical properties of graphene deposited on them was studied using Raman spectroscopy and microwave induced electron transport method. It was found that interaction with the nanowires…

The electronic structure and structural evolution of hydrogenated graphene are investigated by Raman spectroscopy with multiple excitations. The excitation energy dependent saturation effect on the ratio of integrated intensities of D and G…

Materials Science · Physics 2010-12-06 Zhiqiang Luo , Ting Yu , Zhenhua Ni , Sanhua Lim , Jingzhi Shang , Hailong Hu , Lei Liu , Zexiang Shen , Jianyi Lin

We present a systematic experimental and theoretical study of the two-phonon (2D) Raman scattering in graphene under uniaxial tension. The external perturbation unveils that the 2D mode excited with 785nm has a complex line-shape mainly due…

We present detailed multi frequency resonant Raman measurements of potassium graphite intercalation compounds (GICs). From a well controlled and consecutive in-situ intercalation and high temperature de-intercalation approach the response…

Materials Science · Physics 2013-10-25 J. C. Chacon-Torres , L. Wirtz , T. Pichler

Irradiation of graphene on SiO2 by 500 eV Ne and He ions creates defects that cause intervalley scattering as evident from a significant Raman D band intensity. The defect scattering gives a conductivity proportional to charge carrier…

Materials Science · Physics 2009-06-12 Jian-Hao Chen , W. G. Cullen , C. Jang , M. S. Fuhrer , E. D. Williams

We demonstrate theoretically that most of the observed transport properties of graphene sheets at zero magnetic field can be explained by scattering from charged impurities. We find that, contrary to common perception, these properties are…

Mesoscale and Nanoscale Physics · Physics 2008-01-14 Shaffique Adam , E. H. Hwang , Victor Galitski , S. Das Sarma

Graphene with high carrier mobility \mu\ is required both for graphene-based electronic devices and for the investigation of the fundamental properties of graphene's Dirac fermions. It is largely accepted that the mobility-limiting factor…

Mesoscale and Nanoscale Physics · Physics 2012-03-08 A. K. M. Newaz , Yevgeniy S. Puzyrev , Bin Wang , Sokrates T. Pantelides , Kirill I. Bolotin

Understanding disorder in graphene is essential for electronic applications; in contrast to conventional materials, the extraordinarily low electron-phonon scattering1, 2 in graphene implies that disorder3-7 dominates its resistivity even…

Mesoscale and Nanoscale Physics · Physics 2011-11-14 Jun Yan , Michael S. Fuhrer

We consider a double-layer system made of two parallel bilayer graphene sheets separated by a dielectric medium. We calculate the finite-temperature electrical conductivity of the first layer due to charged impurities located in two layers.…

Mesoscale and Nanoscale Physics · Physics 2021-03-09 Dang Khanh Linh , Nguyen Quoc Khanh

We calculate the double resonant (DR) Raman spectrum of graphene, and determine the lines associated to both phonon-defect processes, and two-phonons ones. Phonon and electronic dispersions reproduce calculations based on density functional…

Mesoscale and Nanoscale Physics · Physics 2011-07-26 Pedro Venezuela , Michele Lazzeri , Francesco Mauri