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Various properties of water are affected by confinement as the space-filling of the water molecules is very different from bulk water. In our study, we challenged the creation of a stable system in which water molecules are permanently…

Mesoscale and Nanoscale Physics · Physics 2026-04-28 Tim Verhagen , Jiri Klimes , Barbara Pacakova , Martin Kalbac , Jana Vejpravova

We calculate exactly the vacuum polarization charge density in the field of a subcritical Coulomb impurity, $Z|e|/r$, in graphene. Our analysis is based on the exact electron Green's function, obtained by using the operator method, and…

Mesoscale and Nanoscale Physics · Physics 2008-02-25 Ivan S. Terekhov , Alexander I. Milstein , Valeri N. Kotov , Oleg P. Sushkov

We study fluctuations of the conductance of micron-sized graphene devices as a function of the Fermi energy and magnetic field. The fluctuations are studied in combination with analysis of weak localization which is determined by the same…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 D. W. Horsell , A. K. Savchenko , F. V. Tikhonenko , K. Kechedzhi , I. V. Lerner , V. I. Fal'ko

We have developed a scanning photoluminescence technique that can directly map out the local two-dimensional electron density with a relative accuracy of $\sim2.2\times10^8$ cm$^{-2}$. The validity of this approach is confirmed by the…

The static dielectric function in AA-stacked bilayer graphene (BLG), subjected to an electric field applied perpendicular to layers, is calculated analytically within the random phase approximation (RPA). This result is used to calculate…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 Yawar Mohammadi

In an ideal graphene sheet charge carriers behave as two-dimensional (2D) Dirac fermions governed by the quantum mechanics of massless relativistic particles. This has been confirmed by the discovery of a half-integer quantum Hall effect in…

Materials Science · Physics 2015-05-13 Yuanbo Zhang , Victor W. Brar , Caglar Girit , Alex Zettl , Michael F. Crommie

We present a microscopic theory for interacting graphene armchair nanoribbon quantum dots. Long range interaction processes are responsible for Coulomb blockade and spin-charge separation. Short range ones, arising from the underlying…

Mesoscale and Nanoscale Physics · Physics 2010-03-23 Sonja Koller , Leonhard Mayrhofer , Milena Grifoni

Understanding how the mechanical behavior of materials deviates at the nanoscale from the macroscopically established concepts is a key challenge of particular importance for graphene, given the complex interplay between its nanoscale…

Mesoscale and Nanoscale Physics · Physics 2012-10-26 Levente Tapaszto , Traian Dumitrica , Sung J. Kim , Peter Nemes-Incze , Chanyong Hwang , Laszlo P. Biro

We demonstrate the local oxidation nanopatterning of graphene films by an atomic force microscope. The technique provides a method to form insulating trenches in graphene flakes and to fabricate nanodevices with sub-nm precision. We…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Lishan Weng , Liyuan Zhang , Yong P. Chen , Leonid P. Rokhinson

Using the recently developed technique of microsoldering, we perform a systematic transport study of the influence of PMMA on graphene flakes revealing a doping effect of up to 3.8x10^12 1/cm^2, but a negligible influence on mobility and…

Mesoscale and Nanoscale Physics · Physics 2010-06-10 V. Geringer , D. Subramaniam , A. K. Michel , B. Szafranek , D. Schall , A. Georgi , T. Mashoff , D. Neumaier , M. Liebmann , M. Morgenstern

The derived by us earlier electron scattering matrix for the short-range defects in monolayer graphene is applyed to description of the resistivity electron density dependence. It is argued that large charged defect density is unlikely in…

Mesoscale and Nanoscale Physics · Physics 2011-11-04 Natalie E. Firsova , Sergey A. Ktitorov

A near-field scanning optical microscope is used to locally induce photocurrent in a graphene transistor with high spatial resolution. By analyzing the spatially resolved photo-response, we find that in the n-type conduction regime a p-n-p…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 T. Mueller , F. Xia , M. Freitag , J. Tsang , Ph. Avouris

Since the experimental realization of graphene1, extensive theoretical work has focused on short-range disorder2-5, ''ripples''6, 7, or charged impurities2, 3, 8-13 to explain the conductivity as a function of carrier density…

Other Condensed Matter · Physics 2009-11-13 J. H. Chen , C. Jang , M. S. Fuhrer , E. D. Williams , M. Ishigami

In situ tunable radio-frequency charge detection is used for the determination of the tunneling rates into and out of a graphene single quantum dot connected to only one lead. An analytical model for calculating these rates in the…

Mesoscale and Nanoscale Physics · Physics 2012-07-05 T. Müller , J. Güttinger , D. Bischoff , S. Hellmüller , K. Ensslin , T. Ihn

We measured the conductance fluctuation of bi- and trilayer graphene devices prepared on mechanical exfoliated graphene by an all-dry, lithography-free process using an ultrathin quartz filament as a shadow mask. Reproducible fluctuations…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Neal E. Staley , Conor Puls , Ying Liu

The effect of external static charging of graphene and its flakes are investigated by using first-principles calculations. While the Fermi level of negatively charged graphene rises and then is quickly pinned by the parabolic, nearly free…

Mesoscale and Nanoscale Physics · Physics 2015-03-17 Mehmet Topsakal , Salim Ciraci

Gapless spectrum of graphene allows easy spatial separation of electrons and holes with an external in-plane electric field. Guided collective plasmon modes can propagate along the separation line, whose amplitude decays with the distance…

Mesoscale and Nanoscale Physics · Physics 2012-05-23 N. M. Hassan , V. V. Mkhitaryan , E. G. Mishchenko

Solution-processed few-layers graphene flakes, dispensed to rotating and sliding contacts via liquid dispersions, are gaining increasing attention as friction modifiers to achieve low friction and wear at technologically-relevant…

Mesoscale and Nanoscale Physics · Physics 2023-07-28 Renato Buzio , Andrea Gerbi , Cristina Bernini , Luca Repetto , Andrea Silva , Andrea Vanossi

We compute the tunneling conductance of graphene as measured by a scanning tunneling microscope (STM) with a normal/superconducting tip. We demonstrate that for undoped graphene with zero Fermi energy, the first derivative of the tunneling…

Strongly Correlated Electrons · Physics 2015-05-13 K. Saha , I. Paul , K. Sengupta

We present transport measurements on quantum dots of sizes 45, 60 and 80 nm etched with an Ar/O2-plasma into a single graphene sheet, allowing a size comparison avoiding effects from different graphene flakes. The transport gaps and…

Mesoscale and Nanoscale Physics · Physics 2013-08-01 D. Kölbl , D. M. Zumbühl