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Related papers: Mapping universal conductance fluctuations

200 papers

Graphene holds great potential for superconductivity due to its pure two-dimensional nature, the ability to tune its carrier density through electrostatic gating, and its unique, relativistic-like electronic properties. At present, we are…

Plasmons --the collective oscillations of electrons in conducting materials-- play a pivotal role in nanophotonics because of their ability to couple electronic and photonic degrees of freedom. In particular, plasmons in graphene --the…

Materials Science · Physics 2018-05-08 Renwen Yu , F. Javier García de Abajo

Low temperature magnetoconductance measurements were made in the vicinity of the charge neutrality point. Two origins for the fluctuations were identified close to the CNP. At very low magnetic fields there exist only mesoscopic…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 Simon Branchaud , Alicia Kam , Piotr Zawadzki , Francois M. Peeters , Andrew S. Sachrajda

A beam of holes formed in graphene by a collimating contact is imaged using a liquid-He cooled scanning probe microscope (SPM). The mean free path of holes is greater than the device dimensions. A zigzag shaped pattern on both sides of the…

Mesoscale and Nanoscale Physics · Physics 2020-01-01 Sagar Bhandari , Mary Kreidel , Alexander Kelser , Gil-Ho Lee , Kenji Watanabe , Takashi Taniguchi , Philip Kim , Robert M Westervelt

For many of the envisioned optoelectronic applications of graphene it is crucial to understand the sub-picosecond carrier dynamics immediately following photoexcitation, as well as the effect on the electrical conductivity - the…

Electron transport in graphene is along the sheet but junction devices are often made by stacking different sheets together in a "side-contact" geometry which causes the current to flow perpendicular to the sheets within the device. Such…

Computational Physics · Physics 2015-04-08 Xiang-Guo Li , Iek-Heng Chu , X. -G. Zhang , Hai-Ping Cheng

Graphene has been proposed for use in various nanodevice designs, many of which harness emergent quantum properties for device functionality. However, visualization, measurement, and manipulation become non-trivial at nanometer and atomic…

Mesoscale and Nanoscale Physics · Physics 2022-03-18 Ondrej Dyck , Jacob L. Swett , Charalambos Evangeli , Andrew R. Lupini , Jan A. Mol , Stephen Jesse

A conditional diffusion model has been developed to analyze intricate conductance fluctuations called universal conductance fluctuations or quantum fingerprints appearing in quantum transport phenomena. The model reconstructs impurity…

Mesoscale and Nanoscale Physics · Physics 2025-06-11 Naoto Yokoi , Yuki Tanaka , Yukito Nonaka , Shunsuke Daimon , Junji Haruyama , Eiji Saitoh

We directly image hot spot formation in functioning mono- and bilayer graphene field effect transistors (GFETs) using infrared thermal microscopy. Correlating with an electrical-thermal transport model provides insight into carrier…

Mesoscale and Nanoscale Physics · Physics 2010-12-30 Myung-Ho Bae , Zhun-Yong Ong , David Estrada , Eric Pop

We compare classical versus quantum electron transport in recently investigated magnetic focusing devices [S. Bhandari et al., Nano Lett. 16, 1690 (2016)] exposed to the perturbing potential of a scanning gate microscope (SGM). Using the…

Mesoscale and Nanoscale Physics · Physics 2017-04-26 M. D. Petrović , S. P. Milovanović , F. M. Peeters

We investigate the electron transport in smooth graphene pn junctions, generated by gradually varying electrostatic potentials. The numerically calculated coherent current flow patterns can be understood largely in terms of semi-classical…

Mesoscale and Nanoscale Physics · Physics 2021-01-13 Emmanuel Paredes-Rocha , Yonatan Betancur-Ocampo , Nikodem Szpak , Thomas Stegmann

Using scanning tunneling microscopy, we have imaged local charge density fluctuations in monolayer graphene. By placing a small gold nanoparticle on the end of the STM tip, a charge sensor is created. By raster scanning the tip over the…

Mesoscale and Nanoscale Physics · Physics 2015-03-17 A. Deshpande , W. Bao , H. Zhang , Z. Zhao , C. N. Lau , B. J. LeRoy

Mapping the thermal transport properties of materials at the nanoscale is of critical importance for optimizing heat conduction in nanoscale devices. Several methods to determine the thermal conductivity of materials have been developed,…

Mesoscale and Nanoscale Physics · Physics 2021-03-17 Oliver Braun , Roman Furrer , Pascal Butti , Kishan R. Thodkar , Ivan Shorubalko , Ilaria Zardo , Michel Calame , Mickael L. Perrin

Conductions fluctuations (CF) are studied in single layer graphene devices with superconducting source and drain contacts made from aluminium. The CF are found to be enhanced by superconductivity by a factor of 1.4 to 2. This (near)…

Mesoscale and Nanoscale Physics · Physics 2011-09-19 F. Freitag , J. Trbovic , C. Schönenberger

We investigate the local electron temperature distribution in carbon nano-ribbon (CNR) and graphene junctions subject to an applied thermal gradient. Using a realistic model of a scanning thermal microscope, we predict quantum temperature…

Mesoscale and Nanoscale Physics · Physics 2013-06-21 Justin P. Bergfield , Mark A. Ratner , Charles A. Stafford , Massimiliano Di Ventra

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

The honeycomb lattice of graphene is a unique two-dimensional (2D) system where the quantum mechanics of electrons is equivalent to that of relativistic Dirac fermions. Novel nanometer-scale behavior in this material, including electronic…

Mesoscale and Nanoscale Physics · Physics 2009-05-29 Yuanbo Zhang , Victor W. Brar , Feng Wang , Caglar Girit , Yossi Yayon , Melissa Panlasigui , Alex Zettl , Michael F. Crommie

We report measurements of magnetoresistance in single-layer graphene as a function of gate voltage (carrier density) at 250 mK. By examining signatures of weak localization (WL) and universal conductance fluctuations (UCF), we find a…

Materials Science · Physics 2015-05-14 Yung-Fu Chen , Myung-Ho Bae , Cesar Chialvo , Travis Dirks , Alexey Bezryadin , Nadya Mason

The unconventional properties of graphene, with a massless Dirac band dispersion and large coherence properties, have raised a large interest for applications in nanoelectronics. In this work, we emphasize that graphene two dimensional…

Mesoscale and Nanoscale Physics · Physics 2008-08-27 Pierre Darancet , Valerio Olevano , Didier Mayou

It is commonly believed that weak light-matter interactions in low-mobility graphene dramatically limits tunability of graphene-based optoelectronic devices, such as tunable absorbers or switches. In this paper, we develop and use a simple…

Optics · Physics 2018-12-11 Xuchen Wang , Sergei A. Tretyakov