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Related papers: Graphene Terahertz Absorption

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Monolayer graphene absorbs 2.3 percent of the incident visible light. This 'small' absorption has been used to emphasize the visual transparency of graphene, but it in fact means that multilayer graphene absorbs a sizable fraction of…

Graphene is known as the strongest 2D material in nature, yet we show that moderate charge doping of either electrons or holes can further enhance its ideal strength by up to ~17%, based on first principles calculations. This unusual…

Materials Science · Physics 2015-06-11 Chen Si , Wenhui Duan , Zheng Liu , Feng Liu

Two-dimensional materials offering ultrafast photoresponse suffer from low intrinsic absorbance, especially in the mid-infrared wavelength range. Challenges in 2d material doping further complicate the creation of light-sensitive $p-n$…

We report the near-edge x-ray absorption fine structure (NEXAFS) spectrum of a single layer of graphite (graphene) obtained by micromechanical cleavage of Highly Ordered Pyrolytic Graphite (HOPG) on a SiO2 substrate. We utilized a…

Terahertz (THz) fields are widely applied for sensing, communication and quality control. In future applications, they could be efficiently confined, enhanced and manipulated - well below the classical diffraction limit - through the…

Tunable terahertz plasmons are essential for reconfigurable photonics, which have been demonstrated in graphene through gating, though with relatively weak responses. Here, we demonstrate strong terahertz plasmons in graphite thin films via…

We show that graphene possesses a strong nonlinear optical response in the form of multi-plasmon absorption, with exciting implications in classical and quantum nonlinear optics. Specifically, we predict that graphene nano-ribbons can be…

Mesoscale and Nanoscale Physics · Physics 2015-01-22 Marinko Jablan , Darrick E. Chang

The ultimate aspiration of any detection method is to achieve such a level of sensitivity that individual quanta of a measured value can be resolved. In the case of chemical sensors, the quantum is one atom or molecule. Such resolution has…

Materials Science · Physics 2007-09-06 F. Schedin , A. K. Geim , S. V. Morozov , D. Jiang , E. H. Hill , P. Blake , K. S. Novoselov

Graphene two-dimensional nature combined with today lithography allows to achieve nanoelectronics devices smaller than the Dirac electrons wavelength. Here we show that in these graphene subwavelength nanodevices the electronic quantum…

Mesoscale and Nanoscale Physics · Physics 2010-09-08 Pierre Darancet , Valerio Olevano , Didier Mayou

We study the photoabsorption cross section and Fermi-edge singularities (FES) in graphene. For fillings below one half, we find, besides the expected FES in form of a peaked edge at the threshold (Fermi) energy, a second singularity to…

Mesoscale and Nanoscale Physics · Physics 2011-06-07 Georg Roeder , Grigory Tkachov , Martina Hentschel

We demonstrate that polymer composites with a low loading of graphene, below 1.2 wt. %, are efficient as electromagnetic absorbers in the THz frequency range. The epoxy-based graphene composites were tested at frequencies from 0.25 THz to 4…

We have implemented a generic method, based on the 2n+1 theorem within density functional perturbation theory, to calculate the anharmonic scattering coefficients among three phonons with arbitrary wavevectors. The method is used to study…

Materials Science · Physics 2014-06-24 Lorenzo Paulatto , Francesco Mauri , Michele Lazzeri

We present a general analysis of the influence of nonlinear optical absorption on terahertz generation via optical difference frequency generation, when reaching for the quantum conversion efficiency limit. By casting the equations…

Intersubband transitions in a superlattice under homogeneous electric field is studied within the tight-binding approximation. Since the levels are equi-populated, the non-zero response appears beyond the Born approximation. Calculations…

Disordered Systems and Neural Networks · Physics 2015-06-24 F. T. Vasko

Optical extinction and absorption enhancement in the infrared range of a monolayer graphene sheet by patterning split ring resonators (SRRs) is studied. It is found that the electric mode is stronger in enhancing infrared extinction and…

Optics · Physics 2014-07-31 Yuancheng Fan , Zeyong Wei , Zhengren Zhang , Hongqiang Li

Terahertz (THz) radiation has uses from security to medicine; however, sensitive room-temperature detection of THz is notoriously difficult. The hot-electron photothermoelectric effect in graphene is a promising detection mechanism:…

Graphene-assisted resonant transmission and enhanced Goos-H\"{a}nchen shift are investigated in a two-prism frustrated-total-internal-reflection configuration. Due to the excitation of surface plasmons induced by graphene in low terahertz…

Quantum Physics · Physics 2026-01-13 Yi Chen , Yue Ban , Qi-Biao Zhu , Xi Chen

We investigate 1D aperiodic multilayer microstructures in order to achieve near total absorption in preselected wavelengths in a graphene monolayer. Our structures are designed by a genetic optimization algorithm coupled to a transfer…

Optics · Physics 2018-03-14 Iman Zand , Hamed Dalir , Ray T. Chen , Jonathan P. Dowling

We theoretically investigate the double-resonance Raman spectrum of monolayer graphene down to infrared laser excitation energies. By using first-principles density functional theory calculations, we improve upon previous theoretical…

Mesoscale and Nanoscale Physics · Physics 2025-05-21 Lorenzo Graziotto , Francesco Macheda , Thibault Sohier , Matteo Calandra , Francesco Mauri

The temporal dynamics of charge carriers determines the speed with which electronics can be realized in condensed matter, and their direct manipulation with optical fields promises electronic processing at unprecedented petahertz…