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Related papers: Raman Scattering by sp$^2$ Amorphous Carbons

200 papers

For many materials, Raman spectra are intricately structured and provide valuable information about compositional stoichiometry and crystal quality. Here we use density-functional theory calculations, mass approximation, and the Raman…

Materials Science · Physics 2024-09-04 Nima Ghafari Cherati , I. Abdolhosseini Sarsari , Arsalan Hashemi , Tapio Ala-Nissila

The stacking faults (deviates from Bernal) will break the translational symmetry of multilayer graphenes and modify their electronic and optical behaviors to the extent depending on the interlayer coupling strength. This paper addresses the…

Materials Science · Physics 2015-05-13 Zhenhua Ni , Lei Liu , Yingying Wang , Zhe Zheng , Lain-Jong Li , Ting Yu , Zexiang Shen

We report the observation of an intense anomalous peak at 1608 cm$^{-1}$ in the Raman spectrum of graphene associated to the presence of chromium nanoparticles in contact with graphene. Bombardment with an electron beam demonstrates that…

We report Raman spectra and synchrotron x-ray diffraction measurements of lattice parameters of polycrystalline MgB2 under hydrostatic pressure conditions up to 15 GPa. An anomalously broadened Raman band at 620 cm-1 is observed that…

There are several growing methods for graphene. In this study, the growth of graphene-like clusters on the SiC wafers is done by annealing the wafers in a vacuum evaporation system equipped with a heating source accessory. For evaluating…

Mesoscale and Nanoscale Physics · Physics 2021-05-31 Seyed Sajad Sadeghi , Hamidreza Simchi

We study the polarization-dependent electronic Raman response of untwinned YBa$_2$Cu$_3$O$_{7-\delta}$ superconductors employing a tight-binding band structure with anisotropic hopping matrix parameters and a superconducting gap with a…

Superconductivity · Physics 2007-06-11 Andreas P. Schnyder , Christopher Mudry , Dirk Manske

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

Lattice structure and symmetry of two-dimensional (2D) layered materials are of key importance to their fundamental mechanical, thermal, electronic and optical properties. Raman spectroscopy, as a convenient and nondestructive tool, however…

Mesoscale and Nanoscale Physics · Physics 2015-08-28 Yanqing Feng , Wei Zhou , Yaojia Wang , Jian Zhou , Erfu Liu , Yajun Fu , Zhenhua Ni , Xinglong Wu , Hongtao Yuan , Feng Miao , Baigeng Wang , Xiangang Wan , Dingyu Xing

Surface enhanced Raman spectra from molecules (bipyridyl ethylene) adsorbed on gold dumbells are observed to become increasingly asymmetric (Fano-like) at higher incident light intensity. The electronic temperature (inferred from the…

Mesoscale and Nanoscale Physics · Physics 2016-01-12 S. Dey , M. Banik , E. Hulkko , K. Rodriguez , V. A. Apkarian , M. Galperin , A. Nitzan

The micro-Raman scattering response of a graphene-like location on the surface of bulk natural graphite is investigated both at $T=\unit{4.2}{K}$ and at room temperature in magnetic fields up to 29 T. Two different polarization…

Mesoscale and Nanoscale Physics · Physics 2014-10-03 M. Kuhne , C. Faugeras , P. Kossacki , A. A. L. Nicolet , M. Orlita , Yu. I. Latyshev , M. Potemski

We report results from two-dimensional Raman spectroscopy studies of large-area epitaxial graphene grown on SiC. Our work reveals unexpectedly large variation in Raman peak position across the sample resulting from inhomogeneity in the…

Materials Science · Physics 2015-05-13 J. A. Robinson , C. P. Puls , N. E. Staley , J. Stitt , M. A. Fanton , K. V. Emtsev , T. Seyller , Y. Liu

We argue that Raman scattering in $B_{1g}$ symmetry allows one to distinguish between phonon-mediated and magnetically-mediated $d-$wave superconductivity. In spin mediated superconductors, $B_{1g}$ Raman intensity develops a resonance at a…

Superconductivity · Physics 2009-11-11 A. V. Chubukov , T. P. Devereaux , M. V. Klein

A Raman study of a back gated bilayer graphene sample is presented. The changes in the Fermi level induced by charge transfer splits the Raman G-band, hardening its higher component and softening the lower one. These two components are…

Mesoscale and Nanoscale Physics · Physics 2008-12-16 L. M. Malard , D. C. Elias , E. S. Alves , M. A. Pimenta

Although 2D solids and their vdW heterostructures have garnered much attention recently, their amorphous forms have been less explored. We present a detailed analysis of the structural, electronic, and thermal properties of 2D amorphous…

Materials Science · Physics 2023-05-16 Emel Gürbüz , Biplab Sanyal

We show how the magneto-phonon resonance, particularly pronounced in sp2 carbon allotropes, can be used as a tool to probe the band structure of multilayer graphene specimens. Even when electronic excitations cannot be directly observed,…

Mesoscale and Nanoscale Physics · Physics 2012-09-11 C. Faugeras , P Kossacki , A. A. L. Nicolet , M. Orlita , M Potemski , A. Mahmood , D. M. Basko

2D layered materials have recently attracted tremendous interest due to their fascinating properties and potential applications. The interlayer interactions are much weaker than the intralayer bonds, allowing the as-synthesized materials to…

Materials Science · Physics 2015-04-21 Xin Luo , Chunxiao Cong , Xin Lu , Ting Yu , Qihua Xiong , Su Ying Quek

Recently, the prospects for amorphous phases of graphene (a-G) have been explored computationally. Initial models were flat, and contained odd-member rings, while maintaining three-fold coordination and sp2 bonding. Upon relaxation,…

Disordered Systems and Neural Networks · Physics 2015-06-11 Y. Li , D. A. Drabold

The paper presents detailed Raman scattering study of the unusually broad E2g phonon mode in MgB2 crystal. For the first time, it is shown by the polarized Raman scattering on few-micron-size crystallites with natural faces that the…

Superconductivity · Physics 2012-12-18 J. Hlinka , I. Gregora , J. Pokorny , A. Plecenik , P. Kus , L. Satrapinsky , S. Benacka

It has been long accepted that the second-order Raman bands in carbon nanotubes are enhanced through the double-resonance mechanism. Although separate aspects of this mechanism have been studied for a few second-order Raman bands, including…

Mesoscale and Nanoscale Physics · Physics 2018-08-15 Valentin N. Popov

We analyze the band topology of acoustic phonons in 2D materials by considering the interplay of spatial and internal symmetries with additional constraints that arise from the physical context. These supplemental constraints trace back to…

Mesoscale and Nanoscale Physics · Physics 2022-02-14 Gunnar F. Lange , Adrien Bouhon , Bartomeu Monserrat , Robert-Jan Slager