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Related papers: Dirac excited state quenching in graphene

200 papers

We present an effective hydrodynamic theory of electronic transport in graphene in the interaction-dominated regime. We derive the emergent hydrodynamic description from the microscopic Boltzmann kinetic equation taking into account…

Mesoscale and Nanoscale Physics · Physics 2015-09-23 U. Briskot , M. Schütt , I. V. Gornyi , M. Titov , B. N. Narozhny , A. D. Mirlin

Conducting materials typically exhibit either diffusive or ballistic charge transport. However, when electron-electron interactions dominate, a hydrodynamic regime with viscous charge flow emerges (1-13). More stringent conditions…

We perform a femtosecond-THz optical pump-probe spectroscopy to investigate the cooling dynamics of hot carriers in quasi-free standing bilayer epitaxial graphene. We observed longer decay time constants, in the range of 2.6 to 6.4 ps,…

Mesoscale and Nanoscale Physics · Physics 2023-02-03 Sachin Sharma , Rachael L. Myers-Ward , David Kurt Gaskill , Ioannis Chatzakis

We report an optical study of charge transport in graphene. Diffusion of hot carriers in epitaxial graphene and reduced graphene oxide samples are studied using an ultrafast pump-probe technique with a high spatial resolution.…

Mesoscale and Nanoscale Physics · Physics 2015-03-17 Brian A. Ruzicka , Shuai Wang , Lalani K. Werake , Ben Weintrub , Kian Ping Loh , Hui Zhao

Electrons in isolated graphene layers are a two-dimensional gas of massless Dirac Fermions. In realistic devices, however, the electronic properties are modified by elastic deformations, interlayer coupling and substrate interaction. Here…

It is well established that topological insulators sustain Dirac fermion surface states as a consequence of band inversion in the bulk. These states have a helical spin polarization and a linear dispersion with large Fermi velocity. In this…

The low energy physics of both graphene and surface states of three-dimensional topological insulators is described by gapless Dirac fermions with linear dispersion. In this work, we predict the emergence of a "heavy" Dirac fermion in a…

Mesoscale and Nanoscale Physics · Physics 2016-10-17 Wendong Cao , Rui-Xing Zhang , Peizhe Tang , Gang Yang , Jorge Sofo , Wenhui Duan , Chao-Xing Liu

We develop a general hydrodynamic framework for computing direct current thermal and electric transport in a strongly interacting finite temperature quantum system near a Lorentz-invariant quantum critical point. Our framework is…

Strongly Correlated Electrons · Physics 2016-02-24 Andrew Lucas , Jesse Crossno , Kin Chung Fong , Philip Kim , Subir Sachdev

We study heat transport in normal/superconducting graphene junctions. We find that while the thermal conductance displays the usual exponential dependence on temperature, reflecting the s-wave symmetry of the superconductor, it exhibits an…

Superconductivity · Physics 2009-11-13 Takehito Yokoyama , Jacob Linder , Asle Sudbo

Graphene is a promising candidate for optoelectronic applications such as photodetectors, terahertz imagers, and plasmonic devices. The origin of photoresponse in graphene junctions has been studied extensively and is attributed to either…

Mesoscale and Nanoscale Physics · Physics 2013-01-30 Marcus Freitag , Tony Low , Fengnian Xia , Phaedon Avouris

We have investigated electron dynamics in top gated graphene by measuring the gate admittance of a diffusive graphene capacitor in a broad frequency range as a function of carrier density. The density of states, conductivity and diffusion…

Mesoscale and Nanoscale Physics · Physics 2011-03-24 E. Pallecchi , A. C. Betz , J. Chaste , G. Fève , B. Huard , T. Kontos , J. -M. Berroir , B. Plaçais

Twisted bilayer graphene near the magic angle exhibits remarkably rich electron correlation physics, displaying insulating, magnetic, and superconducting phases. Here, using measurements of the local electronic compressibility, we reveal…

The unusual electrical and optical properties of graphene make it a promising candidate for optoelectronic applications. An important, but as yet unexplored aspect is the role of photo-excited hot carriers in charge and energy transport at…

Mesoscale and Nanoscale Physics · Physics 2011-08-18 Dong Sun , Grant Aivazian , Aaron M. Jones , Wang Yao , David Cobden , Xiaodong Xu

High-mobility graphene hosting massless charge carriers with linear dispersion provides a promising platform for electron optics phenomena. Inspired by the physics of dielectric optical micro-cavities where the photon emission…

Mesoscale and Nanoscale Physics · Physics 2022-12-15 Jule-Katharina Schrepfer , Szu-Chao Chen , Ming-Hao Liu , Klaus Richter , Martina Hentschel

The finite momentum optical response $\sigma({\boldsymbol{q}},\omega)$ of graphene can be probed with the innovative technique of infrared nanoscopy where mid-infrared radiation is confined by an atomic force microscope cantilever tip. In…

Mesoscale and Nanoscale Physics · Physics 2012-05-23 J. P. Carbotte , J. P. F. LeBlanc , E. J. Nicol

The equilibrium optical phonons of graphene are well characterized in terms of anharmonicity and electron-phonon interactions, however their non-equilibrium properties in the presence of hot charge carriers are still not fully explored.…

Mesoscale and Nanoscale Physics · Physics 2018-02-15 C. Ferrante , A. Virga , L. Benfatto , M. Martinati , D. De Fazio , U. Sassi , C. Fasolato , A. K. Ott , P. Postorino , D. Yoon , G. Cerullo , F. Mauri , A. C. Ferrari , T. Scopigno

Following a nonperturbative formulation of strong-field QED developed in our earlier works, and using the Dirac model of the graphene, we construct a reduced QED_{3,2} to describe one species of the Dirac fermions in the graphene…

Mesoscale and Nanoscale Physics · Physics 2023-02-24 S. P. Gavrilov , D. M. Gitman

We have investigated the behavior of the resistance of graphene at the $n=0$ Landau Level in an intense magnetic field $H$. Employing a low-dissipation technique (with power $P<$3 fW), we find that, at low temperature $T$, the resistance at…

Mesoscale and Nanoscale Physics · Physics 2009-04-01 Joseph G. Checkelsky , Lu Li , N. P. Ong

Ever since the initial experimental observation of correlated insulators and superconductivity in the flat Dirac bands of magic angle twisted bilayer graphene, a search for the microscopic description that explains its strong electronic…

Exact stationary solutions of the electron-photon Dirac equation are obtained to describe the strong interaction between massless Dirac fermions in graphene and circularly polarized photons. It follows from them that this interaction forms…

Mesoscale and Nanoscale Physics · Physics 2010-04-26 O. V. Kibis