Electronic spectra, topological states, and impurity effects in graphene nanoribbons

Yu. G. Pogorelov; D. Kochan; V. M. Loktev

doi:10.1063/10.0005798

Electronic spectra, topological states, and impurity effects in graphene nanoribbons

Low Temperature Physics ◽

10.1063/10.0005798 ◽

2021 ◽

Vol 47 (9) ◽

pp. 754-764

Author(s):

Yu. G. Pogorelov ◽

D. Kochan ◽

V. M. Loktev

Keyword(s):

Electronic Spectra ◽

Graphene Nanoribbons ◽

Impurity Effects ◽

Topological States

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Impurity effects on polaron dynamics in graphene nanoribbons

Carbon ◽

10.1016/j.carbon.2015.04.065 ◽

2015 ◽

Vol 91 ◽

pp. 171-177 ◽

Cited By ~ 16

Author(s):

Wiliam Ferreira da Cunha ◽

Luiz Antonio Ribeiro ◽

Antonio Luciano de Almeida Fonseca ◽

Ricardo Gargano ◽

Geraldo Magela e Silva

Keyword(s):

Graphene Nanoribbons ◽

Impurity Effects ◽

Polaron Dynamics

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Manipulating topology in tailored artificial graphene nanoribbons

10.21203/rs.3.rs-409243/v1 ◽

2021 ◽

Author(s):

Nathan Guisinger ◽

Daniel Trainer ◽

Srilok Sriniva ◽

Brandon Fisher ◽

Yuan Zhang ◽

...

Keyword(s):

Graphene Nanoribbons ◽

Research Effort ◽

Copper Surface ◽

Quantum States ◽

Topological Phases ◽

Spintronic Devices ◽

Graphene Derivatives ◽

Topological States ◽

Exotic Physics ◽

Artificial Graphene

Abstract Topological phases of matter give rise to exotic physics that can be leveraged for next generation quantum computation1–3 and spintronic devices4,5. Thus, the search for topological phases and the quantum states that they exhibit have become the subject of a massive research effort in condensed matter physics. Topologically protected states have been produced in a variety of systems, including artificial lattices6–9, graphene nanoribbons (GNRs)10,11 and bismuth bilayers12,13. Despite these advances, the real-time manipulation of individual topological states and their relative coupling, a necessary feature for the realization of topological qubits, remains elusive. Guided by first-principles calculations, we spatially manipulate robust, zero-dimensional topological states by altering the topological invariants of quasi-one-dimensional artificial graphene nanostructures. This is achieved by positioning carbon monoxide molecules on a copper surface to confine its surface state electrons into artificial atoms positioned to emulate the low-energy electronic structure of graphene derivatives. Ultimately, we demonstrate control over the coupling between adjacent topological states that are finely engineered and simulate complex Hamiltonians. Our atomic synthesis gives access to an infinite range of nanoribbon geometries, including those beyond the current reach of synthetic chemistry, and thus provides an ideal platform for the design and study of novel topological and quantum states of matter.

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Topological phase transition in chiral graphene nanoribbons: from edge bands to end states

Nature Communications ◽

10.1038/s41467-021-25688-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jingcheng Li ◽

Sofia Sanz ◽

Nestor Merino-Díez ◽

Manuel Vilas-Varela ◽

Aran Garcia-Lekue ◽

...

Keyword(s):

Phase Transition ◽

Graphene Nanoribbons ◽

Scanning Tunneling ◽

Topological Phase ◽

Tunneling Microscopy ◽

Molecular Precursors ◽

Precise Control ◽

Band Engineering ◽

Topological Phase Transition ◽

Topological States

AbstractPrecise control over the size and shape of graphene nanostructures allows engineering spin-polarized edge and topological states, representing a novel source of non-conventional π-magnetism with promising applications in quantum spintronics. A prerequisite for their emergence is the existence of robust gapped phases, which are difficult to find in extended graphene systems. Here we show that semi-metallic chiral GNRs (chGNRs) narrowed down to nanometer widths undergo a topological phase transition. We fabricated atomically precise chGNRs of different chirality and size by on surface synthesis using predesigned molecular precursors. Combining scanning tunneling microscopy (STM) measurements and theory simulations, we follow the evolution of topological properties and bulk band gap depending on the width, length, and chirality of chGNRs. Our findings represent a new platform for producing topologically protected spin states and demonstrate the potential of connecting chiral edge and defect structure with band engineering.

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