Nonlinear Transport Behaviors in Anti-aromatic Cyclo[n]carbon-based (n = 4k) Molecular Devices

Abstract

Recently, a doubly anti-aromatic cyclo[16]carbon (C₁₆) has been successfully synthesized. Similar to doubly aromatic C_n (n = 4k + 2), anti-aromatic C_n (n = 4k), including C₁₆, feature vertically discrete π-electron conjugate systems, endowing them with unique electronic properties. However, the exploration of transport properties of anti-aromatic C_n-based molecular devices is still in a rudimentary stage. In this study, we report on the electron transport properties of anti-aromatic C_n-based devices with three different types of electrodes, using density functional theory (DFT) combined with the nonequilibrium Green’s function (NEGF) method. Our findings reveal that all devices exhibit nonlinear transport behavior regardless of the electrode used, including current-limiting functions, multiple-negative differential resistance effect (multi-NDR), and current oscillation behaviors. Furthermore, as the number of carbon atoms increases, each type of device shows a discernible pattern in its transport properties. The results reveal the regularity of transport in C_n-based molecular devices and offers theoretical guidance for the development of next generation carbon based molecular devices.