A tunable electronic beam splitter realized with crossed graphene nanoribbons

Graphene nanoribbons (GNRs) are promising components in future nanoelectronics due to the large mobility of graphene electrons and their tunable electronic band gap in combination with recent experimental developments of on-surface chemistry strategies for their growth. Here, we explore a prototype...

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Detalles Bibliográficos
Autores: Brandimarte Mendonça, Pedro|||0000-0002-8762-5876, Engelund, Mads, Papior, Nick|||0000-0003-3038-1855, Garcia-Lekue, Aran|||0000-0001-5556-0898, Frederiksen, Thomas, Sanchez-Portal, Daniel|||0000-0001-6860-8790
Tipo de recurso: artículo
Fecha de publicación:2017
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:225319
Acceso en línea:https://ddd.uab.cat/record/225319
https://dx.doi.org/urn:doi:10.1063/1.4974895
Access Level:acceso abierto
Palabra clave:Electronic band gaps
Experimental development
First principles
Graphene nanoribbons
Graphene nanoribbons (GNRs)
Intersection angles
Realistic conditions
Transport characteristics
Descripción
Sumario:Graphene nanoribbons (GNRs) are promising components in future nanoelectronics due to the large mobility of graphene electrons and their tunable electronic band gap in combination with recent experimental developments of on-surface chemistry strategies for their growth. Here, we explore a prototype 4-terminal semiconducting device formed by two crossed armchair GNRs (AGNRs) using state-of-the-art first-principles transport methods. We analyze in detail the roles of intersection angle, stacking order, inter-GNR separation, GNR width, and finite voltages on the transport characteristics. Interestingly, when the AGNRs intersect at θ=60°, electrons injected from one terminal can be split into two outgoing waves with a tunable ratio around 50% and with almost negligible back-reflection. The split electron wave is found to propagate partly straight across the intersection region in one ribbon and partly in one direction of the other ribbon, i.e., in analogy with an optical beam splitter. Our simulations further identify realistic conditions for which this semiconducting device can act as a mechanically controllable electronic beam splitter with possible applications in carbon-based quantum electronic circuits and electron optics. We rationalize our findings with a simple model suggesting that electronic beam splitters can generally be realized with crossed GNRs.