Bias-Dependent Multichannel Transport in Graphene-Boron Nitride Heterojunction Nanoribbons

Abstract

We designed multinary heterojunctions (Z-GBNR) composed of Z-GNR and Z-BNNR. All possible combinations and interface configurations of binary (Z-GBN[n,m]) and ternary (Z-BNGBN[n, m,n] and Z-GBNG[m,n,m']) heterojunctions were studied to explore the structural effects of the heterojunctions on electron transport properties. Our results reveal that Z-GBNR show characteristic bias-dependent multichannel transport behaviors due to the distinctive response of each electron transport channel. Specifically, the electron transport channels generated on Z-GNR and Z-BNNR exhibited alternating and sequential on/off, which strongly depended on the combinations and interface configurations of the heterojunctions and were related to the edge symmetry of ZGNR and the edge termination of Z-BNNR. We demonstrate that edge-symmetric Z-GNR and B-edged Z-BNNR play a crucial role in the implementation of negative differential resistance (NDR) and stepwise current behaviors in Esaki-like diodes and multivalue logic transistors. Therefore, we propose Z-BNC[4,4] and Z-BNCNB[4,4,4] composed of only B-edged Z-BNNR and symmetric Z-GNR as Esaki-like diodes with bias-dependent alternating on/off behavior for each electron transport channel on Z-BNNR and Z-GNR. We show that Z-CBNC[8,4,6] has cumulatively increased the current in a stepwise manner due to the sequential contribution of each electron transport channel. We believe that our results will provide insights into the design and implementation of various electronic logic functions with multinary heterojunctions of Z-GNR and Z-BNNR based on an understanding of the structure-characteristic relationships for applications in the field of nanoelectronics.