Disorder by order in graphene

Sarma, S. Das; Hwang, E. H.; Li, Qiuzi

doi:10.1103/physrevb.85.195451

Cited by 94 publications

(82 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Anderson localization, intrinsic thermal transport in clean graphene near the Dirac point, and a gap-induced metal-to-insulator transition as proposed in Refs. 64,72, and in the current work, respectively) of the experimental observations in Ref. 64.…”

Section: On the Metal-insulator Transition In Double-layer Graphementioning

confidence: 92%

“…This scenario can be considered a generalization to the case when a finite band-gap is present of the scenario presented in Ref. 72. In this scenario, where the interplay between the SLG band-gap introduced by hBN and the disorder screening by the double-SLG structure dominates transport properties in the system, there is a density-tuned an effective metal-insulator transition from a gapped insulator to an effective metal due to the percolation transition.…”

Section: On the Metal-insulator Transition In Double-layer Graphementioning

confidence: 99%

See 1 more Smart Citation

Ground state of graphene heterostructures in the presence of random charged impurities

et al. 2014

Self Cite

View full text Add to dashboard Cite

We study the effect of long-range disorder created by charge impurities on the carrier density distribution of graphene-based heterostructures. We consider heterostructures formed by two graphenic sheets (either single layer graphene, SLG, or bilayer graphene, BLG) separated by a dielectric film. We present results for symmetric heterostructures, SLG-SLG and BLG-BLG, and hybrid ones, BLG-SLG. As for isolated layers, we find that the presence of charged impurities induces strong carrier density inhomogeneities, especially at low dopings where the density landscape breaks up in electron-hole puddles. We provide quantitative results for the strength of the carrier density inhomogeneities and for the screened disorder potential for a large range of experimentally relevant conditions. For heterostructures in which BLG is present we also present results for the band-gap induced by the perpendicular electric field generated self-consistently by the disorder potential and by the distribution of charges in the heterostructure. For SLG-SLG heterostructures we discuss the relevance of our results for the understanding of the recently observed metal-insulator transition in each of the graphene layers forming the heterostructure. Moreover, we calculate the correlation between the density profiles in the two graphenic layers and show that for standard experimental conditions the two profiles are well correlated.

show abstract

Section: On the Metal-insulator Transition In Double-layer Graphementioning

confidence: 92%

Section: On the Metal-insulator Transition In Double-layer Graphementioning

confidence: 99%

Ground state of graphene heterostructures in the presence of random charged impurities

et al. 2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…A remarkable experiment has however recently demonstrated the possibility to screen out these detrimental effects [113], providing access to the zero-energy Dirac physics. An unexpectedly large increase of the resistivity at the Dirac point was tentatively related to Anderson localization [113,114] of unknown physical origin and questioned interpretation [115]. Of paramount importance are therefore the low-energy impurity states known as zero-energy modes (ZEMs) [116,117], whose impact on the Dirac point trans-port physics needs to be clarified.…”

Section: Transport Properties Of Graphene With Vacancies 411 Introdmentioning

confidence: 99%

Charge and Spin Transport in Disordered Graphene-Based Materials

Tuan

2016

Springer Theses

View full text Add to dashboard Cite

“…The key physical point here is that the strong potential fluctuations induce strong density inhomogeneity with the electrons (or holes) forming spatial puddles separated by potential barriers 59 . We mention here that a large number of 2D experimental 7-10,18-24,26-29 and theoretical [39][40][41][42][54][55][56][57][58][59][60][61][62][63][64] works in the literature have already suggested the 2-component percolation transport as the underlying mechanism for the 2D MIT phenomena.…”

Section: Introductionmentioning

confidence: 99%

“…Thus, there are two independent transport channels in the problem: Diffusive transport by the mobile electrons/holes and activated transport by the trapped electrons/holes. We use a 2-component effective medium theory (EMT) [38][39][40][41][42] , the two components being the fractions of trapped ("activated transport" ) and mobile ("diffusive transport") carriers, to describe the transport behavior in the system. Obviously, high-density transport, when the fraction of mobile carriers is very high, would appear diffusive and metallic, and low-density transport, when the fraction of trapped carriers is very high, would appear activated insulating with a crossover at some disorder-dependent intermediate carrier density.…”

Section: Introductionmentioning

confidence: 99%

Two-dimensional metal-insulator transition as a potential fluctuation driven semiclassical transport phenomenon

Sarma

Hwang

2013

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

We theoretically consider the carrier density tuned (apparent) two-dimensional (2D) metalinsulator-transition (MIT) in semiconductor heterostructure-based 2D carrier systems as arising from a classical percolation phenomenon in the inhomogeneous density landscape created by the long-range potential fluctuations induced by random quenched charged impurities in the environment. The long-range Coulomb disorder inherent in semiconductors produces strong potential fluctuations in the 2D system where a fraction of the carriers gets trapped or classically localized, leading to a mixed 2-component semiclassical transport behavior at intermediate densities where a fraction of the carriers is mobile and another fraction immobile. At high carrier density, all the carriers are essentially mobile whereas at low carrier density all the carriers are essentially trapped since there is no possible percolating transport path through the lake-and-mountain inhomogeneous potential landscape. The low-density situation with no percolation would mimic an insulator whereas the high-density situation with allowed percolating paths through the lake-and-mountain energy landscape would mimic a metal with the system manifesting an apparent MIT in between. We calculate the transport properties as a function of carrier density, impurity density, impurity location, and temperature using a 2-component (trapped and mobile carriers) effective medium theory. Our theoretically calculated transport properties are in good qualitative agreement with the experimentally observed 2D MIT phenomenology in 2D electron and hole systems. We find a high (low) density metallic (insulating) temperature-dependence of the 2D resistivity, and an intermediate-density crossover behavior which could be identified with the experimentally observed 2D MIT. The calculated density-and temperature-dependent resistivity in our theory mimics the phenomenology of 2D MIT experiments with reasonable parameter values for the background disorder.

show abstract

Disorder by order in graphene

Cited by 94 publications

References 50 publications

Ground state of graphene heterostructures in the presence of random charged impurities

Ground state of graphene heterostructures in the presence of random charged impurities

Charge and Spin Transport in Disordered Graphene-Based Materials

Two-dimensional metal-insulator transition as a potential fluctuation driven semiclassical transport phenomenon

Contact Info

Product

Resources

About