English
Related papers

Related papers: Phonon self-energy corrections to non-zero wavevec…

200 papers

We investigate the effect of electron- $\mathrm{A}_{1g}$ phonon coupling on the gapless electronic band dispersion of the pristine graphene. The electron-phonon interaction is introduced through a Kekul\'{e}-type distortion giving rise to…

Mesoscale and Nanoscale Physics · Physics 2013-10-29 B. S. Kandemir , A. Mogulkoc

By considering analytical expressions for the self-energies of intervalley and intravalley phonons in graphene, we describe the behavior of D, 2D, and D$'$ Raman bands with changes in doping ($\mu$) and light excitation energy ($E_L$).…

Mesoscale and Nanoscale Physics · Physics 2013-01-30 K. Sasaki , K. Kato , Y. Tokura , S. Suzuki , T. Sogawa

In neutral graphene, two prominent cusps known as Kohn anomalies are found in the phonon dispersion of the highest optical phonon at $q=\Gamma$ (LO branch) and $q=K$ (TO branch), reflecting a significant electron-phonon coupling to undoped…

Mesoscale and Nanoscale Physics · Physics 2015-08-18 Antonio Politano , Fernando de Juan , Gennaro Chiarello , Herbert A. Fertig

The phonon modes at finite temperature in graphene and single-walled carbon nanotubes (SWCNT) are investigated by the mode projection technique combined with molecular dynamics simulation. It is found that the quadratic phonon spectrum of…

Materials Science · Physics 2011-08-31 Jin-Wu Jiang , Jian-Sheng Wang

We study the effect exerted by the electrons on the flexural phonons in graphene, accounting for the attractive interaction created by the exchange of electron-hole excitations. Combining the self-consistent computation of the phonon…

Mesoscale and Nanoscale Physics · Physics 2010-03-18 Pablo San-Jose , Jose González , Francisco Guinea

We present an analysis of deep-UV Raman measurements of graphite, graphene and carbon nanotubes. For excitation energies above the strong optical absorption peak at the $M$ point in the Brillouin zone ($\approx 4.7\,\text{eV}$), we…

Materials Science · Physics 2015-08-03 Christoph Tyborski , Felix Herziger , Roland Gillen , Janina Maultzsch

Strong electron-phonon interaction which limits electronic mobility of semiconductors can also have significant effects on phonon frequencies. The latter is the key to the use of Raman spectroscopy for nondestructive characterization of…

We examine the intrinsic energy dissipation steps in electrically biased graphene channels. By combining in-situ measurements of the spontaneous optical emission with a Raman spectroscopy study of the graphene sample under conditions of…

Mesoscale and Nanoscale Physics · Physics 2015-03-13 Stéphane Berciaud , Melinda Y. Han , Louis E. Brus , Philip Kim , Tony F. Heinz

Two new Raman modes below 100 cm^-1 are observed in twisted bilayer graphene grown by chemical vapor deposition. The two modes are observed in a small range of twisting angle at which the intensity of the G Raman peak is strongly enhanced,…

Mesoscale and Nanoscale Physics · Physics 2013-08-16 Rui He , Ting-Fung Chung , Conor Delaney , Courtney Keiser , Luis A. Jauregui , Paul M. Shand , C. C. Chancey , Yanan Wang , Jiming Bao , Yong P. Chen

We develop the theory of the non-adiabatic phonon self-energy arising from coupling to electrons with finite linewidths using the spectral representation of Green's functions. Our formalism naturally includes the contribution from the…

Materials Science · Physics 2025-09-18 Cheol-Hwan Park

We report multiphonon Raman scattering in graphene samples. Higher order combination modes involving 3 phonons and 4 phonons are observed in single-layer (SLG), bi-layer (BLG), and few layer (FLG) graphene samples prepared by mechanical…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Rahul Rao , Derek Tishler , Jyoti Katoch , Masa Ishigami

We report a comprehensive micro-Raman scattering study of electrochemically-gated graphene field-effect transistors. The geometrical capacitance of the electrochemical top-gates is accurately determined from dual-gated Raman measurements,…

Mesoscale and Nanoscale Physics · Physics 2016-08-08 Guillaume Froehlicher , Stéphane Berciaud

Electron-phonon interaction and related self-energy are fundamental to both the equilibrium properties and non-equilibrium relaxation dynamics of solids. Although electron-phonon interaction has been suggested by various time-resolved…

Mesoscale and Nanoscale Physics · Physics 2023-05-09 Hongyun Zhang , Changhua Bao , Michael Schüler , Shaohua Zhou , Qian Li , Laipeng Luo , Wei Yao , Zhong Wang , Thomas P. Devereaux , Shuyun Zhou

We present symmetry properties of the lattice vibrations of graphene nanoribbons with pure armchair (AGNR) and zigzag edges (ZGNR). In non-symmorphic nanoribbons the phonon modes at the edge of the Brillouin zone are twofold degenerate,…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 Roland Gillen , Marcel Mohr , Janina Maultzsch

We use first-principles density-functional calculations to determine the frequency shift of the A$'_1$-${\bf K}$ phonon (Raman D band) in monolayer graphene, as a function of the charge doping. A detailed DFT study on the electron-phonon…

Materials Science · Physics 2007-05-23 Srijan Kumar Saha , U. V. Waghmare , H. R. Krishnamurthy , A. K. Sood

Fano resonances and their strong doping dependence are observed in Raman scattering of single-layer graphene (SLG). As the Fermi level is varied by a back-gate bias, the Raman G band of SLG exhibits an asymmetric line shape near the charge…

Mesoscale and Nanoscale Physics · Physics 2013-05-27 Duhee Yoon , Dongchan Jeong , Hu-Jong Lee , Riichiro Saito , Young-Woo Son , Hyun Cheol Lee , Hyeonsik Cheong

The Raman active G mode in graphene exhibits strong coupling to electrons, yet the comprehensive treatment of this interaction in the calculation of its temperature-dependent Raman spectrum remains incomplete. In this study, we calculate…

We describe a peculiar fine structure acquired by the in-plane optical phonon at the Gamma-point in graphene when it is brought into resonance with one of the inter-Landau-level transitions in this material. The effect is most pronounced…

Mesoscale and Nanoscale Physics · Physics 2009-09-24 M. O. Goerbig , J. -N. Fuchs , K. Kechedzhi , Vladimir I. Fal'ko

Magic-angle twisted bilayer graphene (TBG) has attracted significant interest recently due to the discoveries of diverse correlated and topological states in this system. Despite the extensive research on the electron-electron interaction…

Mesoscale and Nanoscale Physics · Physics 2022-10-13 Xiaoqian Liu , Ran Peng , Zhaoru Sun , Jianpeng Liu

Time-resolved Raman spectroscopy has been applied to probe the anharmonic coupling and electron-phonon interaction of optical phonons in graphite. From the decay of the transient anti-Stokes scattering of the G-mode following ultrafast…

Materials Science · Physics 2015-05-14 Hugen Yan , Daohua Song