Engineering quantum spin Hall effect in graphene nanoribbons via edge functionalization

Autès, G.; Yazyev, Oleg V.

doi:10.1103/physrevb.87.241404

Cited by 18 publications

(21 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[32][33][34][35][36][37] There are many theoretical proposals for quantum devices such as, for example, spin valves 38 or quantum spin Hall devices. 39 The experimental realization of most of these suggested devices is, however, not yet possible as they rely on special structures with atomic precision.…”

Section: B Electrons In Graphene Are Specialmentioning

confidence: 99%

Localized charge carriers in graphene nanodevices

Bischoff

Varlet

Simonet

et al. 2015

Applied Physics Reviews

100

View full text Add to dashboard Cite

Graphene—two-dimensional carbon—is a material with unique mechanical, optical, chemical, and electronic properties. Its use in a wide range of applications was therefore suggested. From an electronic point of view, nanostructured graphene is of great interest due to the potential opening of a band gap, applications in quantum devices, and investigations of physical phenomena. Narrow graphene stripes called “nanoribbons” show clearly different electronical transport properties than micron-sized graphene devices. The conductivity is generally reduced and around the charge neutrality point, the conductance is nearly completely suppressed. While various mechanisms can lead to this observed suppression of conductance, disordered edges resulting in localized charge carriers are likely the main cause in a large number of experiments. Localized charge carriers manifest themselves in transport experiments by the appearance of Coulomb blockade diamonds. This review focuses on the mechanisms responsible for this charge localization, on interpreting the transport details, and on discussing the consequences for physics and applications. Effects such as multiple coupled sites of localized charge, cotunneling processes, and excited states are discussed. Also, different geometries of quantum devices are compared. Finally, an outlook is provided, where open questions are addressed.

show abstract

Section: B Electrons In Graphene Are Specialmentioning

confidence: 99%

Localized charge carriers in graphene nanodevices

Bischoff

Varlet

Simonet

et al. 2015

Applied Physics Reviews

100

View full text Add to dashboard Cite

show abstract

“…The intrinsic dangling bonds associated with edge carbon atoms are highly unstable and tend to adsorb atoms, 13,[26][27][28][29][30] molecules 13,31,32 or radical groups. 27,29 Some adatom-terminated GNRs, other than the H-terminated one, are predicted to be stable in theoretical calculations, such as K, 27 F, 20,28 O, 19,24 B, 29 Mg, 29 Ru, 33 Te, 34 and transition-metalterminated GNRs (X-GNRs, X: adatoms). 27,29 Some adatom-terminated GNRs, other than the H-terminated one, are predicted to be stable in theoretical calculations, such as K, 27 F, 20,28 O, 19,24 B, 29 Mg, 29 Ru, 33 Te, 34 and transition-metalterminated GNRs (X-GNRs, X: adatoms).…”

Section: Introductionmentioning

confidence: 99%

Adatom bond-induced geometric and electronic properties of passivated armchair graphene nanoribbons

Lin

Chung

Yang

et al. 2015

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

The geometric and electronic properties of passivated armchair graphene nanoribbons, enriched by strong chemical bonding between edge-carbons and various adatoms, are investigated by first-principle calculations. Adatom arrangements, bond lengths, charge distributions, and energy dispersions are dramatically changed by edge passivation. Elements with an atomic number of less than 20 are classified into three types depending on the optimal geometric structures: planar and non-planar structures, the latter of which are associated with specific arrangements and stacked configurations of adatoms. Especially, the nitrogen passivated nanoribbon is the most stable one with a heptagon-pentagon structure at the edges. The low-lying band structures are drastically varied, exhibiting non-monotonous energy dispersions and adatom-dominated bands. A relationship between energy gaps and ribbon widths no longer exists, and some adatoms further induce a semiconductor-metal transition. All the main characteristics are directly reflected in the density of states, revealing dip structures, plateaus, symmetric peaks, and square-root divergent asymmetric peaks.

show abstract

“…In addition to controlling spin-orbit interaction, to realize quantum spin Hall state in experimental observation, one suggestion is manipulating covalent functionalization of graphene edges with functional groups containing heavy elements [139,140]. Based on Proof-of-concept first-principles calculations, a very strong spin-orbit coupling can be induced in realistic models of narrow graphene nanoribbons with tellurium-terminated edges.…”

Section: Calculations and Suggestions For Spintronics Applicationsmentioning

confidence: 98%

“…Consequently, electronic bands with strong quantum spin Hall could be manipulated. Moreover, this aids us toward engineering topological electronic phases in nanostructures based on graphene and other materials by means of locally introduced spin-orbit interactions [140].…”

Section: Calculations and Suggestions For Spintronics Applicationsmentioning

confidence: 99%