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Related papers: Unique prospects of graphene-based THz modulators

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We demonstrate a high-contrast electro-optic modulation of a photonic crystal nanocavity integrated with an electrically gated monolayer graphene. A high quality (Q) factor air-slot nanocavity design is employed for high overlap between the…

A novel mechanism to realize dynamically tunable electromagnetically induced transparency (EIT) analogue in the terahertz (THz) regime is proposed. By putting the electrically controllable monolayer graphene under the dark resonator, the…

Optics · Physics 2017-12-18 Tingting Liu

Scanning tunneling spectroscopy (STS) has yielded significant insight on the electronic structure of graphene and other two-dimensional (2D) materials. STS directly measures a fundamental and directly calculable quantity: the single…

We proposed multilayered graphene (Gr)-based surface plasmon resonance-induced high-performance terahertz (THz) modulators with tunable resonance frequencies. Several THz plasmonic modulators based on Gr metamaterials were previously…

Optics · Physics 2024-05-17 Dip Sarker , Partha Pratim Nakti , Ahmed Zubair

It was demonstrated that optical modulation together with simultaneous terahertz (THz) imaging application enables an increase in contrast by an order of magnitude illustrating hence the technique as convenient contactless tool for…

In this paper, four easy-to-fabricate graphene-based Si waveguide modulators are presented to overcome the strong polarization dependency of graphene-based modulators. The modulation features of two newly proposed structures, i.e. two…

Optics · Physics 2020-04-10 Mohamad Najafi Hajivar , Mahmood Hosseini-Farzad

Periodic metallic gratings on substrates can support a range of electromagnetic modes, such as leaky waveguide, guided-resonant, and Fabry-Perot (FP) cavity modes, which can strongly modulate optical transmission under resonant excitation.…

We demonstrate efficient terahertz (THz) modulation by coupling graphene strongly with a broadband THz metasurface device. This THz metasurface, made of periodic gold slit arrays, shows near unity broadband transmission, which arises from…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 S. -F. Shi , B. Zeng , H. -L. Han , X. Hong , H. -Z. Tsai , H. S. Jung , A. Zettl , M. F. Crommie , F. Wang

Over the last decade, progress in wide bandgap, III-V materials systems based on gallium nitride (GaN) has been a major driver in the realization of high power and high frequency electronic devices. Since the highly conductive,…

The conductivity of graphene on a boron nitride substrate exhibits features in the terahertz (THz) and infrared (IR) frequency regimes that are associated with the periodic moir\'e pattern formed by the weakly coupled two-dimensional…

Mesoscale and Nanoscale Physics · Physics 2015-10-14 Ashley M. DaSilva , Jeil Jung , Shaffique Adam , Allan H. MacDonald

Metasurfaces offer significant potential to control far-field light propagation through the engineering of amplitude, polarization, and phase at an interface. We report here phase modulation of an electronically reconfigurable metasurface…

The strong light-matter interaction in graphene over a broad frequency range has opened up a plethora of photonics applications of graphene. The goal of this paper is to present the voltage tunability of plasmons in gated single- and…

Materials Science · Physics 2016-01-20 Shaloo Rakheja , Parijat Sengupta

It is commonly believed that weak light-matter interactions in low-mobility graphene dramatically limits tunability of graphene-based optoelectronic devices, such as tunable absorbers or switches. In this paper, we develop and use a simple…

Optics · Physics 2018-12-11 Xuchen Wang , Sergei A. Tretyakov

Much attention has been focused on ways of rendering graphene semiconducting. We study periodically gated graphene in a tight-binding model and find that, contrary to predictions based on the Dirac equation, it is possible to open a band…

Mesoscale and Nanoscale Physics · Physics 2012-10-10 Jesper Goor Pedersen , Thomas Garm Pedersen

We demonstrate tunable solid state and flexible graphene field effect devices (FEDs) fabricated using a poly(methylmethacrylate) (PMMA) and lithium fluoride (LiF) composite dielectric. Increasing the concentration of LiF in the composite…

Mesoscale and Nanoscale Physics · Physics 2016-05-03 Arunandan Kumar , Priyanka Tyagi , Ritu Srivastava

The $\pi$-electronic structure of graphene in the presence of a modulated electric potential is investigated by the tight-binding model. The low-energy electronic properties are strongly affected by the period and field strength. Such a…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 J. H. Ho , Y. H. Chiu , S. J. Tsai , M. F. Lin

Thermal conductivity is a critical material property in numerous applications, such as those related to thermoelectric devices and heat dissipation. Effectively modulating thermal conductivity has become a great concern in the field of heat…

Materials Science · Physics 2023-04-06 Xiao Wan , Dongkai Pan , Jing-Tao Lü , Sebastian Volz , Lifa Zhang , Qing Hao , Yangjun Qin , Zhicheng Zong , Nuo Yang

At low energy, electrons in doped graphene sheets behave like massless Dirac fermions with a Fermi velocity which does not depend on carrier density. Here we show that modulating a two-dimensional electron gas with a long-wavelength…

Mesoscale and Nanoscale Physics · Physics 2009-06-29 M. Gibertini , A. Singha , V. Pellegrini , M. Polini , G. Vignale , A. Pinczuk , L. N. Pfeiffer , K. W. West

In this work, single-layer intrinsic and fluorinated graphene were investigated as gate insertion layers in normally-OFF p-GaN gate HEMTs, which wraps around the bottom of the gate forming Ti/graphene/p-GaN at the bottom and Ti/graphene/…

Applied Physics · Physics 2020-04-22 Guangnan Zhou , Zeyu Wan , Gaiying Yang , Yang Jiang , Robert Sokolovskij , Hongyu Yu , Guangrui , Xia

In order to overcome the challenge of obtaining high modulation depth due to weak graphene-light interaction, a graphene-on-silicon nitride (SiNx) microring resonator based on graphene's gate-tunable optical conductivity is proposed and…