Graphene-Diode-Based Frequency Conversion Mixers for High-Frequency Applications

This paper presents the recent development of graphene-based frequency-conversion mixers for high-frequency applications. The presented circuits are realised employing metal-insulator-graphene (MIG) diodes that are integrated alongside with a monolithic microwave integrated circuit (MMIC) process on a quartz substrate. A single-diode and double-balanced mixers have been designed, fabricated, and characterised in the 2.4 GHz and 10GHz frequency bands, respectively. The characterisation results of the demonstrated circuits promise an excellent performance compared to state-of-the-art graphene field-effect transistors (GFETs) based mixers. In addition, the measured conversion loss of the fabricated mixers competes with the commercial circuits which employ Schottky diodes.