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Related papers: Petahertz optical response in graphene

200 papers

We study broadband terahertz (THz) conductivity and ultrafast photoconductivity spectra in lithographically fabricated multilayer epitaxial graphene nanoribbons grown on C- face of 6H-SiC substrate. THz near-field spectroscopy reveals local…

Materials Science · Physics 2026-03-02 Arvind Singh , Jan Kunc , Tinkara Troha , Hynek Němec , Petr Kužel

Reflectance and transmittance of graphene in the optical region are analyzed as a function of frequency, temperature, and carrier density. We show that the optical graphene properties are determined by the direct interband electron…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 L. A. Falkovsky

Charge carrier scattering is critical to the electrical properties of two-dimensional materials such as graphene, transition metal dichalcogenide monolayers, black phosphorene, and tellurene. Beyond pristine two-dimensional materials,…

Mesoscale and Nanoscale Physics · Physics 2018-09-14 Dongchao Xu , Shuang Tang , Xu Du , Qing Hao

Perfect absorption of radiation in a graphene sheet may play a pivotal role in the realization of technologically relevant optoelectronic devices. In particular, perfect absorption of radiation in the terahertz (THz) spectral range would…

Optics · Physics 2014-11-25 Fangli Liu , Y. D. Chong , Shaffique Adam , Marco Polini

The elecrooptical response of graphene due to heating and drift of carriers is studied theoretically. Real and imaginary parts of the dynamic conductivity tensor are calculated for the case of effective momentum relaxation, when anisotropic…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 M. V. Strikha , F. T. Vasko

We review the transmission of Dirac electrons through a potential barrier in the presence of circularly polarized light. A different type of transmission is demonstrated and explained. Perfect transmission for nearly head-on collision in…

Mesoscale and Nanoscale Physics · Physics 2014-08-28 Godfrey Gumbs , Danhong Huang , Andrii Iurov , Bo Gao

We perform a detailed analysis of electronic polarizability of graphene with different theoretical approaches. From Kubo's linear response formalism, we give a general expression of frequency and wave-vector dependent polarizability within…

Mesoscale and Nanoscale Physics · Physics 2021-03-31 Tao Zhu , Mauro Antezza , Jian-Sheng Wang

We present a trajectory-resolved framework for charge transport in graphene and related two-dimensional carbon systems beyond the ideal ballistic and fully coherent limits. Transport is described by kinetic Monte Carlo hopping on a…

Mesoscale and Nanoscale Physics · Physics 2026-04-20 J. P. Dadario Pereira , Raphael Tromer , Luiz A. Ribeiro Junior , Douglas S. Galvao

Graphene is a two-dimensional layer of carbon atoms arranged in a honeycomb lattice, whose outstanding properties makes it an excellent material for future electronic and photonic terahertz (THz) devices. In this work, we design hybrid…

Optics · Physics 2020-06-29 Tianjing Guo , Christos Argyropoulos

The remarkable electrical, optical and mechanical properties of graphene make it a desirable material for electronics, optoelectronics and quantum applications. A fundamental understanding of the electrical conductivity of graphene across a…

Using ultrafast optical pump-probe spectroscopy, we have measured carrier relaxation times in epitaxial graphene layers grown on SiC wafers. We find two distinct time scales associated with the relaxation of nonequilibrium photogenerated…

Materials Science · Physics 2019-06-05 Jahan M. Dawlaty , Shriram Shivaraman , Mvs Chandrashekhar , Farhan Rana , Michael G. Spencer

Auger scattering channels are of fundamental importance to describe and understand the non-equilibrium charge carrier dynamics in graphene. While impact excitation increases the number of carriers in the conduction band and has been…

The nonequilibrium dynamics of carriers and phonons in graphene is investigated by solving the microscopic kinetic equations with the carrier-phonon and carrier-carrier Coulomb scatterings explicitly included. The Fermi distribution of hot…

Mesoscale and Nanoscale Physics · Physics 2012-03-15 B. Y. Sun , Y. Zhou , M. W. Wu

Graphene as a zero-bandgap two-dimensional semiconductor with a linear electron band dispersion near the Dirac points has the potential to exhibit very interesting nonlinear optical properties. In particular, third harmonic generation of…

Applied Physics · Physics 2018-01-31 Parvin Navaeipour , Ibraheem Al-Naib , Marc M. Dignam

Although massless Dirac fermions in graphene constitute a centrosymmetric medium for in-plane excitations, their second-order nonlinear optical response is nonzero if the effects of spatial dispersion are taken into account. Here we present…

Mesoscale and Nanoscale Physics · Physics 2016-12-07 Yongrui Wang , Mikhail Tokman , Alexey Belyanin

We present measurements of the transient photoconductivity in pentacene single crystals using optical-pump THz-probe spectroscopy. We have measured the temperature and fluence dependence of the mobility of the photoexcited charge carriers…

Condensed Matter · Physics 2016-01-26 V. K. Thorsmolle , R. D. Averitt , X. Chi , D. J. Hilton , D. L. Smith , A. P. Ramirez , A. J. Taylor

Graphene has been shown to exhibit a nonlinear response due to its unique band structure. In this paper, we study the terahertz (THz) response metallic armchair graphene nanoribbons, specifically current density and Rabi oscillations beyond…

Mesoscale and Nanoscale Physics · Physics 2021-07-27 Sawsan Daws , David R. Andersen

It is evidenced by numerical calculations that optically pumped graphene is suitable for compensating inherent loss in terahertz (THz) metamaterials. In a first step, the complex conductivity of graphene under optical pumping is calculated…

Optics · Physics 2015-06-18 Peter Weis , Juan Luis Garcia-Pomar , Marco Rahm

Graphene, a monolayer of carbon atoms arranged in a hexagonal pattern, provides a unique two-dimensional (2D) system exhibiting exotic phenomena such as quantum Hall effects, massless Dirac quasiparticle excitations and universal absorption…

Mesoscale and Nanoscale Physics · Physics 2013-04-23 K. M. Dani , J. Lee , R. Sharma , A. D. Mohite , C. M. Galande , P. M. Ajayan , A. M. Dattelbaum , H. Htoon , A. J. Taylor , R. P. Prasankumar

Third harmonic generation of terahertz radiation is expected to occur in monolayer graphene due to the nonlinear relationship between the crystal momentum and the current density. In this work, we calculate the terahertz nonlinear response…

Applied Physics · Physics 2018-06-22 Parvin Navaeipour , Marc M. Dignam