Print Email Facebook Twitter Electronic Transport in Helium Beam Modified Graphene and Ballistic Josephson Junctions Title Electronic Transport in Helium Beam Modified Graphene and Ballistic Josephson Junctions Author Nanda, G. (TU Delft QN/Kavli Nanolab Delft) Contributor Vandersypen, L.M.K. (promotor) Alkemade, P.F.A. (copromotor) Degree granting institution Delft University of Technology Date 2017-05-16 Abstract This thesis describes the capabilities of the helium ion microscope (HIM) and that of graphene to explore fundamental physics and novel applications. While graphene offers superior electronic properties, the helium ion microscope allows us to combine imaging and modification of materials at the nanoscale. We used the capabilities of HIM to grow 3D-AFM probes, which can be used in the critical dimension semiconductor metrology. Moreover, we studied the ion-material interactions, needed to enable the fabrication of functional graphene nanoribbons. Similarly, we used the superior electronic properties of graphene to make ballistic Josephson junctions and studied the current-phase relation (CPR) of these junctions.The core of this thesis is focused on the fabrication and electronic characterization of He+ beam modified graphene, He+ beam etched graphene nanoribbons, and graphene-based Josephson junctions (JJs). The graphene devices were prepared by a new polymer-free transfer "van der Waals pick-up" technique. The fabricated devices comprise graphene encapsulated in hexagonal boron nitride (BN) and contacted along the edge by either a normalmetal (Cr/Au) or by a superconductor. The encapsulation in BN keeps the graphene clean and the edge contacting technique provides transparent interfaces. The thesis is divided into two main topics. In particular, the first three studies are dedicated to the research based on the helium ion microscope, and the next three are dedicated to the research based on boron nitride encapsulated graphene Josephson junctions. Subject helium ion microscopygraphenebeam-induced depositionion-induced defectsgraphene nanoribbonsJosephson junctionscurrent-phase relationsuperconducting quantum interference devices (SQUIDs) To reference this document use: https://doi.org/10.4233/uuid:342da318-4a11-4989-8c79-df0f0a11468f ISBN 978-90-8593-295-6 Part of collection Institutional Repository Document type doctoral thesis Rights © 2017 G. Nanda Files PDF Thesis_G_Nanda.pdf 17.63 MB Close viewer /islandora/object/uuid:342da318-4a11-4989-8c79-df0f0a11468f/datastream/OBJ/view