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Related papers: Gradient-index electron optics in graphene pn junc…

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Electrons in graphene follow unconventional trajectories at PN junctions, driven by their pseudospintronic degree of freedom. Significant is the prominent angular dependence of transmission, capturing the chiral nature of the electrons and…

Mesoscale and Nanoscale Physics · Physics 2013-05-30 Redwan N. Sajjad , S. Sutar , J. U. Lee , Avik W. Ghosh

The electron transport of different conical valleys is investigated in graphene with extended line-defects. Intriguingly, the electron with a definite incident angle can be completely modulated into one conical valley by a resonator which…

Mesoscale and Nanoscale Physics · Physics 2013-12-02 Yang Liu , Juntao Song , Yuxian Li , Ying Liu , Qing-feng Sun

Mid-infrared spectroscopy is essential for chemical identification and compositional analysis, due to the existence of characteristic molecular absorption fingerprints. However, it is very challenging to determine the refractive index of an…

Optics · Physics 2020-11-16 Xiaofei Xiao , Stefan A. Maier , Vincenzo Giannini

Graphene is considered to be plasmon active only up to the infrared based on combined tight binding model and random phase approximation calculations. Here we show that the optical properties of graphene as measured by ellipsometry and…

Mesoscale and Nanoscale Physics · Physics 2014-04-28 Philipp Lange , Günter Kewes , Nikolai Severin , Oliver Benson , Jürgen P. Rabe

Guiding electronic waves in a manner similar to photon transmission in optical fibers is key for developing the electron-optics toolbox. Here we outline a `weak guiding' approach, in which efficient diffraction around disorder results in…

Mesoscale and Nanoscale Physics · Physics 2015-12-15 Kamphol Akkaravarawong , Oles Shtanko , Leonid Levitov

Q. Ma et al.[1] recently reported a strong photocurrent associated with charge neutrality in graphene devices with non-uniform geometries, which they interpreted as an intrinsic photoresponse enhanced by the momentum non-relaxing nature of…

Mesoscale and Nanoscale Physics · Physics 2020-02-26 Michael S. Fuhrer , Nikhil V. Medhekar

The optical conductivity of graphene strained uniaxially is studied within the Kubo-Greenwood formalism. Focusing on inter-band absorption, we analyze and quantify the breakdown of universal transparency in the visible region of the…

Mesoscale and Nanoscale Physics · Physics 2011-01-17 Vitor M. Pereira , R. M. Ribeiro , N. M. R. Peres , A. H. Castro Neto

We present transport measurements on a bilayer graphene sheet with homogeneous back gate and split top gate. The electronic transport data indicates the capability to direct electron flow through graphene nanostructures purely defined by…

Mesoscale and Nanoscale Physics · Physics 2012-10-10 S. Dröscher , C. Barraud , K. Watanabe , T. Taniguchi , T. Ihn , K. Ensslin

Graphene has emerged as a novel platform for opto-electronic applications and photodetector, but the inefficient conversion from light to current has so far been an important roadblock. The main challenge has been to increase the light…

We present a detailed numerical study of the electronic properties of single-layer graphene with resonant ("hydrogen") impurities and vacancies within a framework of noninteracting tight-binding model on a honeycomb lattice. The algorithms…

Mesoscale and Nanoscale Physics · Physics 2010-09-29 Shengjun Yuan , Hans De Raedt , Mikhail I. Katsnelson

This paper is devoted to the inverse design of strained graphene surfaces for the control of electrons in the semi-classical optical-like regime. Assuming that charge carriers are described by the Dirac equation in curved-space and…

Mesoscale and Nanoscale Physics · Physics 2021-12-03 E. Lorin , F. Fillion-Gourdeau , S. Maclean

We have integrated on oxidized silicon wafers superconductive films and Josephson junctions along with sol-gel optical channel waveguides. The fabrication process is carried out in two steps that result to be solid and non-invasive. It is…

Superconductivity · Physics 2009-11-13 F. Stella , M. Casalboni , M. Cirillo , V. Merlo , C. Palazzesi , G. P. Pepe , P. Prosposito , M. Salvato

Conductance of zigzag interfaces between graphene sheet and normal metal is investigated in the tight-binding approximation. Boundary conditions, valid for a variety of scattering problems, are constructed and applied to the normal metal --…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Ya. M. Blanter , Ivar Martin

The versatile control of graphene's plasmonic modes via an external gate-voltage inspires us to design efficient electro-optical graphene plasmonic logic gates at the midinfrared wavelengths. We show that these devices are superior to the…

Mesoscale and Nanoscale Physics · Physics 2014-05-08 Kelvin J. A. Ooi , Hong Son Chu , Ping Bai , Lay Kee Ang

Graphene has shown great application opportunities in future nanoelectronic devices due to its outstanding electronic properties. Moreover, its impressive optical properties have been attracting the interest of researchers, and, recently,…

Graphene is believed to be an excellent candidate material for next-generation electronic devices. However, one needs to take into account the nontrivial effect of metal contacts in order to precisely control the charge injection and…

Mesoscale and Nanoscale Physics · Physics 2013-10-08 Salvador Barraza-Lopez , Markus Kindermann , M. Y. Chou

Interference of standing waves in electromagnetic resonators forms the basis of many technologies, from telecommunications and spectroscopy to detection of gravitational waves. However, unlike the confinement of light waves in vacuum, the…

The observation of quantum conductance oscillations in mesoscopic systems has traditionally required the confinement of the carriers to a phase space of reduced dimensionality. While electron optics such as lensing and focusing have been…

Mesoscale and Nanoscale Physics · Physics 2009-03-20 Andrea F. Young , Philip Kim

The interaction between doped graphene nanoislands connected by narrow junctions constitutes an ideal testbed to probe quantum effects in plasmonic systems. Here, the interaction between graphene plasmons in neighboring nanoislands is…

Mesoscale and Nanoscale Physics · Physics 2013-03-11 Sukosin Thongrattanasiri , Alejandro Manjavacas , Peter Nordlander , F. Javier Garcia de Abajo

Tunneling of quasiparticles between two nearly-aligned graphene sheets produces resonant current-voltage characteristics because of the quasi-exact conservation of in-plane momentum. We claim that, in this regime, vertical transport in…

Mesoscale and Nanoscale Physics · Physics 2016-03-29 Karina A. Guerrero-Becerra , Andrea Tomadin , Marco Polini