A tunable electronic beam splitter realized with crossed graphene nanoribbons
Brandimarte Mendonça, Pedro (Centro de Física de Materiales)
Engelund, Mads (Centro de Física de Materiales)
Papior, Nick (Institut Català de Nanociència i Nanotecnologia)
Garcia-Lekue, Aran (Basque Foundation for Science)
Frederiksen, Thomas (Basque Foundation for Science)
Sanchez-Portal, Daniel (Donostia International Physics Center)

Date:	2017
Abstract:	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.
Grants:	European Commission 676598 European Commission 610446 Ministerio de Economía y Competitividad MAT2013-46593-C6-2-P
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Electronic band gaps ; Experimental development ; First principles ; Graphene nanoribbons ; Graphene nanoribbons (GNRs) ; Intersection angles ; Realistic conditions ; Transport characteristics
Published in:	Journal of chemical physics, Vol. 146, Issue 9 (March 2017) , art. 92318, ISSN 1089-7690

DOI: 10.1063/1.4974895

15 p, 11.6 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles