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Related papers: Spectra of Half-Infinite Quantum Graph Tubes

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The curvature effects in carbon nanotubes are studied analytically as a function of chirality. The pi-orbitals are found to be significantly rehybridized in all tubes, so that they are never normal to the tubes' surface. This results in a…

Strongly Correlated Electrons · Physics 2009-11-07 Alex Kleiner , Sebastian Eggert

Carbon nanotube networks are one of the candidate materials to function as malleable, transparent, conducting films, with the technologically promising application of being used as flexible electronic displays. Nanotubes disorderly…

Mesoscale and Nanoscale Physics · Physics 2013-02-22 Luiz F. C. Pereira , M. S. Ferreira

We describe a simple lattice model of higher-curvature quantum gravity in two dimensions and study the phase structure of the theory as a function of the curvature coupling. It is shown that the ensemble of flat graphs is entropically…

High Energy Physics - Theory · Physics 2010-02-03 Richard J. Szabo , John F. Wheater

A two-field model provides an unifying framework for elasticity, lattice dynamics and electromechanical coupling in graphene and carbon nanotubes, describes optical phonons, nontrivial acoustic branches, strain-induced gap opening,…

Materials Science · Physics 2009-11-13 Cristiano Nisoli , Paul E. Lammert , Eric Mockensturm , Vincent H. Crespi

Recently, Lagos et al. (Nature Nanotechnology 4, 149 (2009)) reported the discovery of the smallest possible silver square cross-section nanotube. A natural question is whether similar carbon nanotubes can exist. In this work we report ab…

Chemical Physics · Physics 2010-10-06 P A S Autreto , S B Legoas , M Z S Flores , D S Galvao

We describe a new class of scattering matrices for quantum graphs in which back-scattering is prohibited. We discuss some properties of quantum graphs with these scattering matrices and explain the advantages and interest in their study. We…

Mathematical Physics · Physics 2009-11-13 J. M. Harrison , U. Smilansky , B. Winn

The control of the quantum transport is an issue of current interest for the construction of new devices. In this work, we investigate this possibility in the realm of quantum graphs. The study allows the identification of two distinct…

Quantum Physics · Physics 2020-06-05 A. Drinko , F. M. Andrade , D. Bazeia

Nowadays sp carbon chains terminated by graphene or graphitic-like carbon are synthesized routinely in several nanotech labs. We propose an ab-initio study of such carbon-only materials, by computing their structure and stability, as well…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Ivano E. Castelli , Nicola Ferri , Giovanni Onida , Nicola Manini

Motivated by a recent application of quantum graphs to model the anomalous Hall effect we discuss quantum graphs the vertices of which exhibit a preferred orientation. We describe an example of such a vertex coupling and analyze the…

Mathematical Physics · Physics 2019-12-10 Pavel Exner , Milos Tater

A great efficacy of molecular quantum chemistry applied to basic graphene problems has been recently demonstrated by the authors when studying the formation of peculiar composites between carbon nanotubes and graphene as well as considering…

Mesoscale and Nanoscale Physics · Physics 2011-02-07 Elena F Sheka , Nadezhda A Popova

A pristine suspended carbon nanotube is a near ideal environment to host long-lived quantum states. For this reason, they have been used as the core element of qubits and to explore numerous condensed matter physics phenomena. One of the…

Applied Physics · Physics 2024-01-09 Tim Althuon , Tino Cubaynes , Aljoscha Auer , Christoph Sürgers , Wolfgang Wernsdorfer

We analyze the nonlinear optics of quasi one-dimensional quantum graphs and manipulate their topology and geometry to generate for the first time nonlinearities in a simple system approaching the fundamental limits of the first and second…

Optics · Physics 2014-01-28 Rick Lytel , Shoresh Shafei , Julian H. Smith , Mark G. Kuzyk

The band gap of a semiconducting single wall carbon nanotube decreases and eventually vanishes leading to metalization as a result of increasing radial deformation. This sets in a band offset between the undeformed and deformed regions of a…

Materials Science · Physics 2009-10-31 C. Kilic , S. Ciraci , O. Gulseren , T. Yildirim

Graphene nanoribbons (GNRs) are a family of one-dimensional (1D) materials carved from graphene lattice. GNRs possess high mobility and current carrying capability, sizable bandgap, and versatile electronic properties tailored by the…

Mesoscale and Nanoscale Physics · Physics 2021-10-08 Haomin Wang , Hui Shan Wang , Chuanxu Ma , Lingxiu Chen , Chengxin Jiang , Chen Chen , Xiaoming Xie , An-Ping Li , Xinran Wang

Carbon nanotubes provide a unique system to study one-dimensional quantization phenomena. Scanning tunneling microscopy is used to observe the electronic wave functions that correspond to quantized energy levels in short metallic carbon…

Using von Neumann algebras, we extend the theory of quantum computation on a graph to a theory of computation on an arbitrary topological space.

Operator Algebras · Mathematics 2024-07-23 Kazuki Ikeda

Graphene quantum dots are considered as promising alternatives to quantum dots in III-V semiconductors, e.g., for the use as spin qubits due to their consistency made of light atoms including spin-free nuclei which both imply relatively…

Mesoscale and Nanoscale Physics · Physics 2016-04-20 Markus Morgenstern , Nils Freitag , Aviral Vaid , Marco Pratzer , Marcus Liebmann

Carbon foams are hypothetical carbon allotropes that contain graphite-like (sp$^2$ carbon) segments, connected by sp$^3$ carbon atoms, resulting in porous structures. In this work the DFTB (Density Functional based Tight-Binding) method…

Materials Science · Physics 2013-02-15 Gotthard Seifert , Agnieszka Kuc , Thomas Heine

Recent developments of theoretical studies on spin nanotubes are reviewed, especially focusing on the $S=1/2$ three-leg spin tube. In contrast to the three-leg spin ladder, the tube has a spin gap in case of the regular-triangle unit…

Statistical Mechanics · Physics 2010-10-11 Toru Sakai , Masahiro Sato , Kouichi Okunishi , Kiyomi Okamoto , Chigak Itoi

Quantum graphs have recently emerged as models of nonlinear optical, quantum confined systems with exquisite topological sensitivity and the potential for predicting structures with an intrinsic, off-resonance response approaching the…

Optics · Physics 2013-05-21 Rick Lytel , Shoresh Shafei , Mark G. Kuzyk