Query: Electronic transport in two-dimensional graphene

Candidate papers:

abstract: We provide a broad review of fundamental electronic properties of two dimensional graphene with the emphasis on density and temperature dependent carrier transport in doped or gated graphene structures. A salient feature of our review is a critical comparison between carrier transport in graphene and in two dimensional semiconductor systems (e.g. heterostructures, quantum wells, inversion layers) so that the unique features of graphene electronic properties arising from its gap less, massless, chiral Dirac spectrum are highlighted. Experiment and theory as well as quantum and semi classical transport are discussed in a synergistic manner in order to provide a unified and comprehensive perspective. Although the emphasis of the review is on those aspects of graphene transport where reasonable consensus exists in the literature, open questions are discussed as well. Various physical mechanisms controlling transport are described in depth including long range charged impurity scattering, screening, short range defect scattering, phonon scattering, many body effects, Klein tunneling, minimum conductivity at the Dirac point, electron hole puddle formation, p n junctions, localization, percolation, quantum classical crossover, midgap states, quantum Hall effects, and other phenomena.
author_names: Sankar Das Sarma

Shaffique Adam

E H Hwang

Enrico Rossi
title: Electronic transport in two dimensional graphene
year: 2011

abstract: 1 Universite Catholique de Louvain (UCL) Institute of Condensed Matter and Nanoscience (IMCN) Place Croix du Sud 1 (NAPS Boltzmann) 1348 Louvain la Neuve, Belgium 2 European Theoretical Spectroscopy Facility (ETSF) 3 University of Cambridge, Cavendish Laboratory, Theory of Condensed Matter group, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom 4 Institut Catala de Nanotecnologia (ICN) and CIN2, UAB Campus, E 08193 Barcelona, Spain 5 Institucio Catalana de Recerca i Estudis Avancats (ICREA) 08010 Barcelona, Spain and 6 CEA UJF, INAC, SP2M/L_Sim, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
author_names: Aurelien Lherbier

Simon M -M Dubois

Xavier Declerck

Stephan Roche

Yann-Michel Niquet

Jean-Christophe Charlier
title: Electronic transport in two dimensional Graphene with structural defects
year: 2011

abstract: Two dimensional (2D) materials have captured the attention of the scientific community due to the wide range of unique properties at nanometer scale thicknesses. While significant exploratory research in 2D materials has been achieved, the understanding of 2D electronic transport and carrier dynamics remains in a nascent stage. Furthermore, because prior review articles have provided general overviews of 2D materials or specifically focused on charge transport in graphene, here we instead highlight charge transport mechanisms in post graphene 2D materials, with particular emphasis on transition metal dichalcogenides and black phosphorus. For these systems, we delineate the intricacies of electronic transport, including band structure control with thickness and external fields, valley polarization, scattering mechanisms, electrical contacts, and doping. In addition, electronic interactions between 2D materials are considered in the form of van der Waals heterojunctions and composite films. This review concludes with a perspective on the most promising future directions in this fast evolving field.
author_names: Vinod K Sangwan

Mark C Hersam
title: Electronic Transport in Two Dimensional Materials.
venue: Annual review of physical chemistry
year: 2018

abstract: Transport of carriers in two dimensional graphene at high electric fields is investigated by combining semianalytical and Monte Carlo methods. A semianalytical high field transport model based on the high rate of optical phonon emission provides useful estimates of the saturation currents in graphene. For developing a more accurate picture, the nonequilibrium (hot) phonon effect and the role of electron electron scattering were studied using Monte Carlo simulations. Monte Carlo simulations indicate that the hot phonon effect plays a dominant role in current saturation, and electron electron scattering strongly thermalizes the hot carrier population in graphene. We also find that electron electron scattering removes negative differential resistance in graphene. Transient phenomenon such as velocity overshoot can be used to speed up graphene based high speed electronic devices by shrinking the channel length below 80 nm if electrostatic control can be exercised in the absence of a band gap.
author_names: Tian Fang

Aniruddha Konar

Huili Grace Xing

Debdeep Jena
title: High field transport in two dimensional graphene
year: 2011

abstract: We calculate the temperature dependent conductivity of graphene in the presence of randomly distributed Coulomb impurity charges arising from the temperature dependent screening of the Coulomb disorder without any phonons. The purely electronic temperature dependence of our theory arises from two independent mechanisms: the explicit temperature dependence of the finite temperature dielectric function \ensuremath{\epsilon}(q,T) and the finite temperature energy averaging of the transport scattering time. We find that the calculated temperature dependent conductivity is nonmonotonic, decreasing with temperature at low temperatures, and increasing at high temperatures. We provide a critical comparison with the corresponding physics in semiconductor based parabolic band 2D electron gas systems.
author_names: E H Hwang

Sankar Das Sarma
title: Screening induced temperature dependent transport in two dimensional graphene
year: 2009

abstract: We discuss some basic physical properties of electron transport in two dimensional materials. First, we discuss how the predicted thermodynamic instability of 2D crystals may influence charge transport via the coupling of electrons with acoustic flexural modes. We then review the properties of suspended and supported graphene and its ribbons and consider the problem of evaluating correctly the electron phonon coupling in the case of phosphorene. Finally, we discuss the main features of 2D topological insulators and their possible use in transistors.
author_names: Massimo V Fischetti

W G Vandehberghe
title: Physics of electronic transport in two dimensional materials for future FETs
venue: 2016 IEEE International Electron Devices Meeting (IEDM)
year: 2016

abstract: Two dimensional superlattices are promising alternatives to traditional semiconductors for manufacturing power dissipating devices with enhanced thermal and electronic properties. The goal of this work is to investigate the influence of the superlattice secondary periodicity and atomic interface orientation on the phonon properties and thermal conductivity of two dimensional superlattices of graphene and boron nitride. We have employed harmonic lattice dynamics to predict the phonon group velocities and specific heats, and molecular dynamics to extract the relaxation times from normal mode analysis in the frequency domain. Density functional perturbation theory is applied to validate the phonon dispersion curves. The Boltzmann transport equation under single relaxation time approximation is then used to predict the thermal conductivities of the superlattices in the zigzag and armchair orientations with periodicities between one and five. Our results showed that the thermal conductivities increased by 15.68% when reducing the superlattice period from two to one. In addition, thermal conductivities parallel to the interface increase by 20.15% when switching the orientation from armchair to zigzag.Copyright (c) 2015 by ASME
author_names: Carlos da Silva

Fernan Saiz

David A Romero

Cristina H Amon
title: Predicting Phonon Thermal Transport in Two Dimensional Graphene Boron Nitride Superlattices at the Short Period Limit
year: 2015

abstract: Nanoscience offers a unique opportunity to design modern materials from the bottom up via low cost, solution processed assembly of nanoscale building blocks. These systems promise electronic band structure engineering using not only the nanoscale structural modulation, but also the mesoscale spatial patterning, although experimental realization of the latter has been challenging. Here, we design and fabricate a new type of artificial solid by stacking graphene on a self assembled, nearly periodic array of nanospheres, and experimentally observe superlattice miniband effects. We find conductance dips at commensurate fillings of charge carriers per superlattice unit cell, which are key features of minibands that are induced by the quasi periodic deformation of the graphene lattice. These dips become stronger when the lattice strain is larger. Using a tight binding model, we simulate the effect of lattice deformation as a parameter affecting the inter atomic hopping integral, and confirm the superlattice transport behavior. This 2D material nanoparticle heterostructure enables facile band structure engineering via self assembly, promising for large area electronics and optoelectronics applications.Electronic transport: a 2D artificial solid shows superlattice miniband effectsA hybrid heterostructure of self assembled nanoparticles on graphene displays conductance dips due to superlattice miniband effects. A team led by Yingjie Zhang and Nadya Mason at the University of Illinois designed and fabricated a large area artificial solid combining self assembled dielectric nanospheres and graphene grown by chemical vapor deposition. Taking advantage of the structural versatility of SiO2 nanoparticle assembly and the high mobility of graphene, the resulting heterostructure displays miniband effects in the electronic transport characteristics as a result of superlattice formation. Due to the size variability and imperfect ordering of the nanospheres, a broadening was observed in the miniband density of states. This effect can find an application in optoelectronic devices, such as optical modulators and sensor, requiring broadband modulation of their optical spectrum.
author_names: Yingjie Zhang

Youngseok Kim

Matthew J Gilbert

Nadya Mason
title: Electronic transport in a two dimensional superlattice engineered via self assembled nanostructures
venue: npj 2D Materials and Applications
year: 2018

abstract: Two dimensional photonic crystals, in analogy to AB/BA stacking bilayer graphene in electronic system, are studied. Inequivalent valleys in the momentum space for photons can be manipulated by simply engineering diameters of cylinders in a honeycomb lattice. The inequivalent valleys in photonic crystal are selectively excited by a designed optical chiral source and bulk valley polarizations are visualized. Unidirectional valley interface states are proved to exist on a domain wall connecting two photonic crystals with different valley Chern numbers. With the similar optical vortex index, interface states can couple with bulk valley polarizations and thus valley filter and valley coupler can be designed. Our simple dielectric PC scheme can help to exploit the valley degree of freedom for future optical devices.
author_names: Yuting Yang

Hua Jiang

Zhi Hong Hang
title: Topological Valley Transport in Two dimensional Honeycomb Photonic Crystals
venue: Scientific Reports
year: 2018

abstract: After the first unequivocal demonstration of spin transport in graphene (Tombros et al. 2007) surprisingly at room temperature, it was quickly realized that this novel material was relevant for both fundamental spintronics and future applications. Over the decade since, exciting results have made the field of graphene spintronics blossom, and a second generation of studies has extended to new two dimensional (2D) compounds. This Colloquium reviews recent theoretical and experimental advances on electronic spin transport in graphene and related 2D materials, focusing on emergent phenomena in van der Waals heterostructures and the new perspectives provided by them. These phenomena include proximity enabled spin orbit effects, the coupling of electronic spin to light, electrical tunability, and 2D magnetism.
author_names: Ahmet Avsar

H Ochoa

Francisco Guinea

Bart Jan van Wees

Ivan J Vera-Marun
title: Colloquium: Spintronics in graphene and other two dimensional materials
year: 2020