Quantum transport properties of zigzag graphene nanoribbons

Takaki, Hirokazu; Kobayashi, Nobuhiko

doi:10.1016/j.physe.2010.07.035

Cited by 8 publications

(6 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to their intriguing topologies, MGNRs have attracted extensive attention from the research community. Theoretical predictions of their electronic 8–10 , magnetic 11,12 , transport 13 , and thermal 14,15 properties have been made in recent years. Furthermore, MGNRs were predicted to behave as topological insulators 16,17 .…”

Section: Introductionmentioning

confidence: 99%

Electronic Properties of Möbius Cyclacenes Studied by Thermally-Assisted-Occupation Density Functional Theory

Chung

Chai

2019

Sci Rep

View full text Add to dashboard Cite

It has been extremely difficult for traditional theoretical methods to adequately predict the properties of systems possessing radical character (i.e., multi-reference systems), especially for multi-reference systems at the nanoscale. To circumvent this, we employ thermally-assisted-occupation density functional theory (TAO-DFT) to predict the electronic properties of Möbius cyclacenes, with the number of fused benzene rings ( n ) ranging from 8 to 100. In addition, to investigate the significance of Möbius topology, we also compare these properties with the respective properties of cyclacenes and acenes, containing the same number of fused benzene rings. From our TAO-DFT results, Möbius cyclacenes, cyclacenes, and acenes have singlet ground states for all the cases examined. However, unlike acenes, the electronic properties of Möbius cyclacenes and cyclacenes display clear oscillation patterns when n is small (e.g., n ≤ 10 for Möbius cyclacenes and n ≤ 23 for cyclacenes), and converge to the respective properties of acenes when n greatly exceeds 30. The polyradical character of the ground states of Möbius cyclacenes should increase with the molecular size, intimately correlated with the localization of active orbitals at the edges of molecules.

show abstract

Section: Introductionmentioning

confidence: 99%

Electronic Properties of Möbius Cyclacenes Studied by Thermally-Assisted-Occupation Density Functional Theory

Chung

Chai

2019

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Understanding charge transport in graphene nanoribbons (GNRs) has attracted significant interest in recent years [1][2][3][4][5][6][7][8][9][10][11][12], in particular due to their potential application as integrated circuits [13] and field-effect transistors [14][15][16], as bio-sensing devices [17][18][19] and for deoxyribonucleic acid (DNA) sequencing [20][21][22][23]. These unprecedented opportunities have been made possible by experimental advances in creating sub-10 nm wide GNRs [24], in engineering GNRs with specific electronic structures [25], in fabricating high purity samples [26] and in designing artificial molecular graphene [27].…”

Section: Introductionmentioning

confidence: 99%

“…Previous theoretical studies investigating the transport properties of GNRs have predominantly focused on the bias dependent conductance [1][2][3][4][5][6][7][8]10]. Spatial current patterns were investigated in the vicinity of the Fermi energy of half-filled GNRs in the wide-lead limit both for zero-magnetic field [3] and for non-zero magnetic fields and disorder [28].…”

Section: Introductionmentioning

confidence: 99%

Spatial current patterns, dephasing and current imaging in graphene nanoribbons

2014

View full text Add to dashboard Cite

Using the non-equilibrium Keldysh Green's function formalism, we investigate the local, non-equilibrium charge transport in graphene nanoribbons (GNRs). In particular, we demonstrate that the spatial current patterns associated with discrete transmission resonances sensitively depend on the GNRs' geometry, size and aspect ratio, the location and number of leads and the presence of dephasing. We identify a relation between the spatial form of the current patterns, and the number of degenerate energy states participating in the charge transport. Furthermore, we demonstrate a principle of superposition for the conductance and spatial current patterns in multiple-lead configurations. We demonstrate that scanning tunneling microscopy can be employed to image spatial current paths in GNRs with atomic resolution, providing important insight into the form of local charge transport. Finally, we investigate the effects of dephasing on the spatial current patterns, and show that with decreasing dephasing time, the current patterns evolve smoothly from those of a ballistic quantum network to those of a classical resistor network.

show abstract

“…Understanding charge transport in graphene nanoribbons (GNRs) has attracted significant interest in recent years [1,2,3,4,5,6,7,8,9,10,11,12], in particular due to their potential application as integrated circuits [13] and field-effect transistors [14,15,16], as bio-sensing devices [17,18,19], and for DNA sequencing [20,21,22,23]. These unprecedented opportunities have been made possible by experimental advances in creating sub-10nm wide GNRs [24], in engineering GNRs with specific electronic structures [25], in fabricating high purity samples [26], and in designing artificial molecular graphene [27].…”

Section: Introductionmentioning

confidence: 99%

“…Previous theoretical studies investigating the transport properties of GNRs have predominantly focused on the bias dependent conductance [1,2,3,4,5,6,7,8,10]. Spatial current patterns were investigated in the vicinity of the Fermi energy of half-filled GNRs in the wide-lead limit both for zero-magnetic field [3] and for non-zero magnetic fields and disorder [28].…”

Section: Introductionmentioning

confidence: 99%

Spatial Current Patterns, Dephasing and Current Imaging in Graphene Nanoribbons

Mabillard,

Can,

Morr

2014

Preprint

View full text Add to dashboard Cite

Using the non-equilibrium Keldysh Green's function formalism, we investigate the local, non-equilibrium charge transport in graphene nanoribbons (GNRs). In particular, we demonstrate that the spatial current patterns associated with discrete transmission resonances sensitively depend on the GNRs' geometry, size, and aspect ratio, the location and number of leads, and the presence of dephasing. We identify a relation between the spatial form of the current patterns, and the number of degenerate energy states participating in the charge transport. Furthermore, we demonstrate a principle of superposition for the conductance and spatial current patterns in multiple-lead configurations. We demonstrate that scanning tunneling microscopy (STM) can be employed to image spatial current paths in GNR with atomic resolution, providing important insight into the form of local charge transport. Finally, we investigate the effects of dephasing on the spatial current patterns, and show that with decreasing dephasing time, the current patterns evolve smoothly from those of a ballistic quantum network to those of classical resistor network.

show abstract

Quantum transport properties of zigzag graphene nanoribbons

Cited by 8 publications

References 7 publications

Electronic Properties of Möbius Cyclacenes Studied by Thermally-Assisted-Occupation Density Functional Theory

Electronic Properties of Möbius Cyclacenes Studied by Thermally-Assisted-Occupation Density Functional Theory

Spatial current patterns, dephasing and current imaging in graphene nanoribbons

Spatial Current Patterns, Dephasing and Current Imaging in Graphene Nanoribbons

Contact Info

Product

Resources

About