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Related papers: Unique prospects of graphene-based THz modulators

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High performance integrated electro-optic modulators operating at low temperature are critical for optical interconnects in cryogenic applications. Existing integrated modulators, however, suffer from reduced modulation efficiency or…

Dynamic wavelength tunability has long been the holy grail of photodetector technology. Because of its atomic thickness and unique properties, graphene opens up new paradigms to realize this concept, but so far this has been elusive…

Mesoscale and Nanoscale Physics · Physics 2017-03-08 François Léonard , Catalin D. Spataru , Michael Goldflam , David W. Peters , Thomas E. Beechem

The potential of graphene for use in photonic applications was evidenced by recent demonstrations of modulators, polarisation rotators, and isolators. These promising yet preliminary results raise crucial questions: what is the optimal…

Graphene provides a unique platform for hosting high quality 2D electron systems. Encapsulating graphene with hexagonal boron nitride (hBN) to shield it from noisy environments offers the potential to achieve ultrahigh performance…

Mesoscale and Nanoscale Physics · Physics 2024-07-22 Won Beom Choi , Youngoh Son , Hangyeol Park , Yungi Jeong , Junhyeok Oh , K. Watanabe , T. Taniguchi , Joonho Jang

Graphene has remarkable opportunities for spintronics due to its high mobility and long spin diffusion length, especially when encapsulated in hexagonal boron nitride (h-BN). Here, for the first time, we demonstrate gate-tunable spin…

Mesoscale and Nanoscale Physics · Physics 2018-07-25 Jinsong Xu , Simranjeet Singh , Jyoti Katoch , Guanzhong Wu , Tiancong Zhu , Igor Zutic , Roland K. Kawakami

Graphene is promising for nanoscale, efficient, ultra-fast photo- and opto-electronic devices because of its remarkable electrical and optical properties, such as fast electron relaxation and heat dissipation. Here, we realize…

We perform self-consistent Schr\"odinger-Poisson calculations with exchange and correlation corrections to determine the electron/hole gas in a radial hetero-junction formed in a modulation doped GaAs/AlGaAs core-multi-shell nanowire (CSNW)…

Mesoscale and Nanoscale Physics · Physics 2016-04-29 Andrea Bertoni , Miquel Royo , Farah Mahawish , Guido Goldoni

Hybrids of graphene and two dimensional transition metal dichalcogenides (TMDC) have the potential to bring graphene spintronics to the next level. As we show here by performing first-principles calculations of graphene on monolayer…

Mesoscale and Nanoscale Physics · Physics 2015-10-14 Martin Gmitra , Jaroslav Fabian

We observe a strong polarization dependent optical loss of in-plane light propagation in silicon waveguide due to the presence of graphene. Both transverse-electric (TE) and transverse-magnetic (TM) modes are efficiently (~3 dB) coupled to…

We demonstrate a method of making a very shallow, gateable, undoped 2-dimensional electron gas. We have developed a method of making very low resistivity contacts to these structures and systematically studied the evolution of the mobility…

Mesoscale and Nanoscale Physics · Physics 2021-09-17 W. Y. Mak , K. Das Gupta , H. E. Beere , I. Farrer , F. Sfigakis , D. A. Ritchie

Graphene is a sturdy and chemically inert material exhibiting an exposed two-dimensional electron gas of high mobility. These combined properties enable the design of graphene composites either based on covalent or non- covalent coupling of…

Mesoscale and Nanoscale Physics · Physics 2015-03-19 Adrien Allain , Zheng Han , Vincent Bouchiat

Two-dimensional (2D) semiconductors are widely recognized as attractive channel materials for low-power electronics. However, an unresolved challenge is the integration of high-quality, ultrathin high-\k{appa} dielectrics that fully meet…

The heterointerfaces at complex oxides have emerged as a promising platform for discovering novel physical phenomena and advancing integrated sensing, storage, and computing technologies. Nevertheless, achieving precise control over a…

Materials Science · Physics 2025-09-01 Jiaxin Lv , Silan Li , Chenhao Duan , Shuanhu Wang , Hong Yan , Kexin Jin

Opening a sizable band gap in the zero-gap germanene without heavy loss of carrier mobility is a key issue for its application in nanoelectronic devices such as high-performance field effect transistors (FETs) operating at room temperature.…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 Meng Ye , Ruge Quhe , Jiaxin Zheng , Zeyuan Ni , Yangyang Wang , Yakun Yuan , Geoffrey Tse , Junjie Shi , Zhengxiang Gao , Jing Lu

Van der Waals (vdW) structures of two-dimensional materials host a broad range of physical phenomena. New opportunities arise if different functional layers may be remotely modulated or coupled in a device structure. Here we demonstrate the…

Recently High Electron Mobility Transistor (HEMT) inspired III-V electro-optic modulator topologies were proposed for realizing high speed electro-optic modulators leveraging plasma dispersion effect due to the 2D Electron Gas (2DEG)…

Applied Physics · Physics 2020-12-01 Pallabi Das , Shlok Vaibhav Singh , Siddharth Tallur

Half-integer conductance, the signature of Majorana edge modes, has been recently observed in a quantum anomalous Hall insulator/superconductor heterostructure. Here, we analyze a scheme for gate-tunable control of degenerate ground states…

Mesoscale and Nanoscale Physics · Physics 2018-07-10 Nima Djavid , Gen Yin , Yafis Barlas , Roger Lake

Two-dimensional carbon, or graphene, is a semi-metal that presents unusual low-energy electronic excitations described in terms of Dirac fermions. We analyze in a self-consistent way the effects of localized (impurities or vacancies) and…

Strongly Correlated Electrons · Physics 2009-11-11 N. M. R. Peres , F. Guinea , A. H. Castro Neto

The absence of a band-gap in graphene limits the gate modulation of its electron conductivity, both in regular graphene as well as in PN junctions, where electrostatic barriers prove transparent to Klein tunneling. We demonstrate a novel…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Redwan Sajjad , Avik Ghosh

The ability to transport energy is a fundamental property of the two-dimensional Dirac fermions in graphene. Electronic thermal transport in this system is relatively unexplored and is expected to show unique fundamental properties and to…

Mesoscale and Nanoscale Physics · Physics 2013-08-13 K. C. Fong , Emma Wollman , Harish Ravi , Wei Chen , Aash Clerk , M. D. Shaw , H. G. LeDuc , K. C. Schwab