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Related papers: Ultrafast optical currents in gapped graphene

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Graphene is an ideal material to study fundamental Coulomb- and phonon-induced carrier scattering processes. Its remarkable gapless and linear band structure opens up new carrier relaxation channels. In particular, Auger scattering bridging…

We demonstrate a new, nonlinear optical effect of electric currents. First, a steady current is generated by applying a voltage on a doped GaAs crystal. We demonstrate that this current induces second-harmonic generation of a probe laser…

Materials Science · Physics 2015-06-03 Brian A. Ruzicka , Lalani K. Werake , Guowei Xu , Jacob B. Khurgin , E. Ya. Sherman , Judy Z. Wu , Hui Zhao

Direct generation of ultrashort, transform-limited pulses in a laser resonator is observed theoretically and experimentally. This constitutes a new type of ultrashort pulse generation in mode-locked lasers: in contrast to the well-known…

Optics · Physics 2009-11-02 L. M. Zhao , D. Y. Tang , T. H. Cheng

We theoretically study the interaction of an ultrafast intense linearly polarized optical pulse with monolayers of transition metal dichalcogenides (TMDCs). Such a strong pulse redistributes electrons between the bands and generates…

Mesoscale and Nanoscale Physics · Physics 2021-04-21 S. Azar Oliaei Motlagh , Vadym Apalkov , Mark I. Stockman

We investigate the spectral features of the emission from a superluminal polarization current whose distribution pattern rotates with an angular frequency $\omega$ and oscillates with an incommensurate frequency $\Omega >\omega$. This type…

Optics · Physics 2009-11-07 H. Ardavan , A. Ardavan , J. Singleton

Inelastic electron tunneling provides a low-energy pathway for the excitation of surface plasmons and light emission. We theoretically investigate tunnel junctions based on metals and graphene. We show that graphene is potentially a highly…

Mesoscale and Nanoscale Physics · Physics 2015-08-28 Kelvin J. A. Ooi , Hong Son Chu , Chang Yu Hsieh , Dawn T. H. Tan , Lay Kee Ang

The highly unidirectional excitation of graphene plasmons (GPs) through near-field interference of orthogonally polarized dipoles is investigated. The preferred excitation direction of GPs by a single circularly polarized dipole can be…

Mesoscale and Nanoscale Physics · Physics 2016-09-21 Lei Wang , Wei Cai , Xinzheng Zhang , Jingjun Xu , Yongsong Luo

Local magnetic moments can be created in graphene by incorporating different defects. The possibility of regulating dynamics of magnetization in graphene, by employing the Purcell effect, is analyzed. The role of the system parameters in…

Mesoscale and Nanoscale Physics · Physics 2016-01-13 V. I. Yukalov , V. K. Henner , T. S. Belozerova

Ultrafast electron dynamics in solids under strong optical fields has recently found particular attention. In dielectrics and semiconductors, various light-field-driven effects have been explored, such as high-harmonic generation,…

We develop a theory for graphene magnetotransport in the presence of carrier spin polarization as induced, for example, by the application of an in-plane magnetic field ($B$) parallel to the 2D graphene layer. We predict a negative…

Mesoscale and Nanoscale Physics · Physics 2009-08-14 E. H. Hwang , S. Das Sarma

Radiation-induced ratchet electric currents have been studied theoretically in graphene with a periodic noncentrosymmetric lateral potential. The ratchet current generated under normal incidence is shown to consist of two contributions, one…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 A. V. Nalitov , L. E. Golub , E. L. Ivchenko

Electron transport in graphene is along the sheet but junction devices are often made by stacking different sheets together in a "side-contact" geometry which causes the current to flow perpendicular to the sheets within the device. Such…

Computational Physics · Physics 2015-04-08 Xiang-Guo Li , Iek-Heng Chu , X. -G. Zhang , Hai-Ping Cheng

Optical harmonic generation occurs when high intensity light ($>10^{10}$W/m$^{2}$) interacts with a nonlinear material. Electrical control of the nonlinear optical response enables applications such as gate-tunable switches and frequency…

High-order frequency mixing in graphene using a two-color radiation field consisting of the fundamental and the second harmonic fields of an ultrashort linearly polarized laser pulse is studied. It is shown that the harmonics originated…

Mesoscale and Nanoscale Physics · Physics 2022-05-25 Hamlet K. Avetissian , Garnik F. Mkrtchian , Andreas Knorr

Graphene possesses remarkable electronic, optical and mechanical properties that have taken the research of two-dimensional relativistic condensed matter systems to prolific levels. However, the understanding of how its nonlinear optical…

Mesoscale and Nanoscale Physics · Physics 2018-05-23 David N. Carvalho , Andrea Marini , Fabio Biancalana

For many of the envisioned optoelectronic applications of graphene it is crucial to understand the sub-picosecond carrier dynamics immediately following photoexcitation, as well as the effect on the electrical conductivity - the…

We observe photocurrents induced in single layer graphene samples by illumination of the graphene edges with circularly polarized terahertz radiation at normal incidence. The photocurrent flows along the sample edges and forms a vortex. Its…

The independence of the dynamic conductivity of intrinsic graphene of frequency takes its origin in the compensation of the vanishing density of states by the diverging matrix element of the corresponding interband transition. The…

Mesoscale and Nanoscale Physics · Physics 2009-12-08 E. G. Mishchenko

Ultrafast control of electron dynamics in solid state systems has recently found particular attention. By increasing the electric field strength of laser pulses, the light-matter interaction in solids might turn from a perturbative into a…

The process of coherent creation of particle - hole excitations by an electric field in graphene is quantitatively described beyond linear response. We calculate the evolution of current density, number of pairs and energy in ballistic…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 B. Rosenstein , M. Lewkowicz , H. C. Kao , Y. Korniyenko