Synthesis of a tunable MgB2/Nano-Graphene/MgB2–Josephson junction-like structure for electronic devices

Abstract

The present investigations show a new trend, introducing the possibility of forming superconductor/conductor/superconductor Josephson junction-like structure using MgB₂ as a model for the superconducting species and layered graphene for the conducting species. The MgB₂/Graphene/MgB₂ junction was synthesized in three steps, firstly MgB₂ was synthesized by a conventional solid state reaction in a nitrogenated sealed tantalum ampoule. Secondly, a chemical vapor deposition (ICVD) technique was applied to deposit a few layers of graphene on the surfaces of two identical smoothly polished pellets of MgB₂ with the same diameter and thickness. Thirdly, the two pellets with deposited graphene layers were formulated into one pellet using a hydrostatic compressor at 4 Ton cm⁻². The structural and nano-structural features of the resulting interference junction were investigated by Raman spectra, XRD, AFM/STM and SE-microscopy with EDX-analysis. It was concluded that the manufactured MgB₂/Graphene/MgB₂ junction was controlled by many parameters.