Robust negative differential resistance and abnormal magnetoresistance effects in heteroatom-substituted zigzag γ-graphyne nanoribbon homojunctions

Abstract

The electronic, magnetic and transport properties of pristine and chemically modified zigzag γ-graphyne nanoribbons (ZγGYNRs) and corresponding homojunctions are theoretically investigated in the present study. The results show that a pristine ZγGYNR displays similar electronic and magnetic properties to zigzag graphene nanoribbons and these properties can be effectively modulated by substitution of O, B or N atoms. Although the designed ZγGYNR homojunctions have simple structures, they can exhibit rich transport properties such as tunneling magnetoresistance (TMR), negative differential resistance (NDR), abnormal magnetoresistance (AMR) and spin-filtering effects. After O, B or N substitution, the TMR and spin-filtering effects of homojunctions are enhanced and, more importantly, the NDR and AMR effects still exist, indicating that ZγGYNR homojunctions have robust NDR and AMR effects. These intriguing transport properties endow the ZγGYNR homojunctions with potential for applications in future nanoelectronic and spintronic devices.