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Related papers: Unique prospects of graphene-based THz modulators

200 papers

Gate-tunable spin-dependent properties could be induced in graphene at room temperature through magnetic proximity effect by placing it in contact with a metallic ferromagnet. Because strong chemical bonding with the metallic substrate…

Mesoscale and Nanoscale Physics · Physics 2020-11-17 Mihovil Bosnar , Ivor Lončarić , P. Lazić , K. D. Belashchenko , Igor Žutić

For optical communication, information is converted between optical and electrical signal domains at a high rate. The devices to achieve such a conversion are various types of electro-optical modulators and photodetectors. These two types…

Optics · Physics 2015-06-18 Nathan Youngblood , Yoska Anugrah , Rui Ma , Steven J. Koester , Mo Li

We demonstrate a considerable suppression of the low-field leakage through a Y2O3 topgate insulator on graphene by applying high-pressure O2 at 100 atm during post-deposition annealing (HP-PDA). Consequently, the quantum capacitance…

Materials Science · Physics 2015-06-18 Kaoru Kanayama , Kosuke Nagashio , Tomonori Nishimura , Akira Toriumi

By exploiting singular spatial modulations of the graphene conductivity, we design a broadband, tunable THz absorber whose efficiency approaches the theoretical upper bound for a wide absorption band with a fractional bandwidth of 185\%.…

Mesoscale and Nanoscale Physics · Physics 2018-10-25 Emanuele Galiffi , John Pendry , Paloma Arroyo Huidobro

Germanane (GeH) is essentially a hydrogen-terminated Ge analog of graphene with a direct gap (~1.6 eV). Record hole mobility mu_h~67,000 cm2/Vs is found at 15 K for a single allotropic cross-dimensional(D) heterointerface. This is enabled…

Materials Science · Physics 2026-01-09 Yumiko Katayama , Daiki Kobayashi , Hikaru Okuma , Yuhsuke Yasutake , Susumu Fukatsu , Kazunori Ueno

Exerting well-defined control over the reflection $(R)$, absorption $(A)$, and transmission $(T)$ of electromagnetic waves is a key objective in quantum optics. To this end, one often utilizes hybrid structures comprised of elements with…

Optics · Physics 2016-12-06 Jacob Linder , Klaus Halterman

We performed detailed studies of the current-voltage characteristics in graphene/MoS2/metal vertical field-effect transistors. Owing to its low density of states, the Fermi level in graphene is very sensitive to its carrier density and thus…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 Rai Moriya , Takehiro Yamaguchi , Yoshihisa Inoue , Yohta Sata , Sei Morikawa , Satoru Masubuchi , Tomoki Machida

Graphene has generated exceptional interest as an optoelectronic material because its high carrier mobility and broadband absorption promise to make extremely fast and broadband electro-optic devices possible. Electro-optic graphene…

Metal-oxide-semiconductor field-effect transistors (MOSFET's) using atomic-layer-deposited (ALD) Al$_2$O$_3$ as the gate dielectric are fabricated on the Si/Si$_{1-x}$Ge$_x$ heterostructures. The low-temperature carrier density of a…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 K. Lai , P. D. Ye , W. Pan , D. C. Tsui , S. A. Lyon , M. Muhlberger , F. Schaffler

We demonstrate a vertical field-effect transistor based on a graphene/MoSe2 van der Waals (vdW) heterostructure. The vdW interface between the graphene and MoSe2 exhibits a Schottky barrier with an ideality factor of around 1.3, suggesting…

Mesoscale and Nanoscale Physics · Physics 2015-07-21 Yohta Sata , Rai Moriya , Sei Morikawa , Naoto Yabuki , Satoru Masubuchi , Tomoki Machida

We present an extensive study of resonant two-dimensional (2D) plasmon excitations in grating-gated quantum well heterostructures, which enable an electrical control of periodic charge carrier density profile. Our study combines theoretical…

Graphene-based terahertz (THz) devices have emerged as promising platforms for a variety of applications, leveraging graphene's unique optoelectronic properties. This review explores recent advancements in utilizing graphene in THz…

We analyze the operation of the hot-electron FET bolometers with the graphene channels (GCs) and the gate barrier layers (BLs). Such bolometers use the thermionic emission of the hot electrons heated by incident modulated THz radiation. The…

Mesoscale and Nanoscale Physics · Physics 2024-03-12 V. Ryzhii , C. Tang , T. Otsuji , M. Ryzhii , V. Mitin , M. S. Shur

Graphene is a unique platform for tunable opto-electronic applications thanks to its linear band dispersion, which allows electrical control of resonant light-matter interactions. Tuning the nonlinear optical response of graphene is…

A tunable graphene-based reflective cell operating at THz is proposed for use in reconfigurable-beam reflectarrays, or similarly to implement the so-called generalized law of reflection. The change in the complex conductivity of graphene…

Two-dimensional (2D) materials have recently been the focus of extensive research. By following a similar trend as graphene, other 2D materials including transition metal dichalcogenides (MX2) and metal mono-chalcogenides (MX) show great…

Electrons moving in graphene behave as massless Dirac fermions, and they exhibit fascinating low-frequency electrical transport phenomena. Their dynamic response, however, is little known at frequencies above one terahertz (THz). Such…

Van der Waals heterostructures have emerged as a versatile platform to study correlated and topological electron physics. Spectroscopy experiments in the THz regime are crucial, since the energy of THz photons matches that of relevant…

Coupled hybrid nanostructures are demonstrated using the combination of lithographically patterned graphene on top of a two-dimensional electron gas (2DEG) buried in a GaAs/AlGaAs heterostructure. The graphene forms Schottky barriers at the…

Over the years, great efforts have been devoted in introducing a sizable and tunable band gap in graphene for its potential application in next-generation electronic devices. The primary challenge in modulating this gap has been the absence…