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Related papers: Graphene Terahertz Absorption

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Optical properties of graphene are explored by using the generalized tight-binding model. The main features of spectral structures, the form, frequency, number and intensity, are greatly enriched by the complex relationship among the…

Computational Physics · Physics 2016-07-20 Chiun-Yan Lin , Thi-Nga Do , Yao-Kung Huang , Ming-Fa Lin

We investigated ultrafast carrier dynamics in graphene with near-infrared transient absorption measurement after intense half-cycle terahertz pulse excitation. The terahertz electric field efficiently drives the carriers, inducing large…

Mesoscale and Nanoscale Physics · Physics 2012-06-08 Shuntaro Tani , François Blanchard , Koichiro Tanaka

Despite the now vast body of two-dimensional materials under study, bilayer graphene remains unique in two ways: it hosts a simultaneously tunable band gap and electron density; and stems from simple fabrication methods. These two…

Mesoscale and Nanoscale Physics · Physics 2016-07-19 M. K. Brinkley , D. S. L. Abergel , B. D. Clader

Among its many outstanding properties, graphene supports terahertz surface plasma waves -- sub-wavelength charge density oscillations connected with electromagnetic fields that are tightly localized near the surface[1,2]. When these waves…

Plasmon oscillations have been intensively studied for more than forty years in conventional two-dimensional electron gas systems in order to find new alternatives to the vacuum devices based on the Smith-Purcell effect in the far-infrared…

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

Saturable absorption is a non-perturbative nonlinear optical phenomenon that plays a pivotal role in the generation of ultrafast light pulses. Here we show that this effect emerges in graphene at unprecedentedly low light intensities, thus…

Mesoscale and Nanoscale Physics · Physics 2017-03-15 A. Marini , J. D. Cox , F. J. Garcia de Abajo

The theory of optical effects in hydrogenated graphene (graphane) in terahertz and infrared range is developed, including the analysis of complex conductivity, reflection coefficient for graphane on a substrate and dispersion of surface…

Mesoscale and Nanoscale Physics · Physics 2022-10-19 E. I. Preobrazhensky , I. V. Oladyshkin , M. D. Tokman

We investigate the absorption properties of graphene-based anisotropic metamaterial structures where the metamaterial layer possesses an electromagnetic response corresponding to a near-zero permittivity. We find that through analytical and…

Optics · Physics 2016-08-25 Jacob Linder , Klaus Halterman

The transient response of an intrinsic graphene, which is caused by the ultrafast interband transitions, is studied theoretically for the range of pumping correspondent to the saturated absorption regime. Spectral and temporal dependencies…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 F. T. Vasko

The absorption of heavily doped graphene in the terahertz (THz) and mid-infrared (MIR) spectral regions is considered taking into account both the elastic scattering due to finite-range disorder and the variations of concentration due to…

Materials Science · Physics 2015-06-11 F. T. Vasko , V. V. Mitin , V. Ryzhii , T. Otsuji

The past decade has seen rapid growth in the research area of graphene and its application to novel electronics. With Moore's law beginning to plateau, the need for post-silicon technology in industry is becoming more apparent. Moreover,…

Mesoscale and Nanoscale Physics · Physics 2021-07-22 Mohamed Warda , Khodr Badih

Exploration of optical non-linear response of graphene predominantly relies on ultra-short time domain measurements. Here we propose an alternate technique that uses frequency modulated continuous wavefront optical fields, thereby probing…

Mesoscale and Nanoscale Physics · Physics 2019-03-18 Ashutosh Singh , Saikat Ghosh , Amit Agarwal

We demonstrate greatly enhanced light absorption by monolayer graphene over a broad spectral range, from visible to near infrared, based on the attenuated total reflection. In the experiment, graphene is sandwiched between two dielectric…

Optics · Physics 2013-10-01 Wangshi Zhao , Kaifeng Shi , Zhaolin Lu

Hypersound amplification/absorption of acoustic phonons in Graphene with degenerate energy dispersion $\varepsilon(p)$ near the Fermi level was theoretically studied. For $k_{\beta}T << 1$ and $ql >> 1$, the dependence of the absorption…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 Kwadwo A. Dompreh , Natalia G. Mensah , Samuel Y. Mensah

Graphene is an attractive material for broadband photodetection but suffers from weak light absorption. Coating graphene with quantum dots can significantly enhance light absorption and create extraordinarily high photo gain. This high gain…

Mesoscale and Nanoscale Physics · Physics 2020-12-04 Kaixiang Chen , Chufan Zhang , Xiaoxian Zang , Fuyuan Ma , Yuanzhen Chen , Yaping Dan

We employ the first-principles GW+Bethe Salpeter equation approach to study the electronic structure and optical absorption spectra of uniaxial strained graphene with many-electron effects included. Applied strain not only induces an…

Materials Science · Physics 2015-05-30 Yufeng Liang , Shouting Huang , Li Yang

The electronic structure and optical response of electrically gated bilayer graphene are studied by first-principles approaches. We have obtained the induced band gap that is in good agreement with experiment when the applied electric field…

Mesoscale and Nanoscale Physics · Physics 2015-03-13 Li Yang

Van der Waals heterostructures obtained by artificially stacking two-dimensional crystals represent the frontier of material engineering, demonstrating properties superior to those of the starting materials. Fine control of the interlayer…

Terahertz (THz) technology shows great potential in 6G communications and imaging, but faces challenges related to detector sensitivity, noise, and cryogenic operation. Here, we integrate interferometric enhancement of absorption (IEA) from…

Mesoscale and Nanoscale Physics · Physics 2025-12-30 Runli Li , Shaojing Liu , Ximiao Wang , Hongjia Zhu , Yongsheng Zhu , Shangdong Li , Huanjun Chen