Investigation on the electrical and transport properties of phosphorene antidot nanoribbons for nanoscale applications
ABSTRACT :
In this era where novel materials and/or new device formulations are necessary for low power and high performance devices, 2D materials play a significant role due to their advanced structural, electronic and magnetic properties. The realization of 2D materials started with graphene which excited material scientists due to its strong mechanical and astonishing electronic properties owing to massless Dirac fermions. Although there are many exceptional electrical properties, the zero bandgap for pure 2D graphene becomes a hurdle to cope with in switching applications. This problem forced researchers to either invent techniques to introduce a bandgap into graphene or to look for other 2D materials beyond graphene. Graphene nanoribbons (GNRs), a small 1D section of graphene, having a layer width dependent bandgap, found their way into device applications. Other 2D materials (MoS2, BN, silicene, phosphorene etc.,) are also extensively researched with promising mobility and device performance index. In this work, we examine the prospect of phosphorene antidot nanoribbons (PANRs) using the density functional based tight binding (DFTB) method. Horizontally perforated PANRs with both armchair (A) and zigzag (Z) configurations were considered for electrical simulations. From the simulation results we found that the APANRs cannot be scaled down with nanoribbon width, whereas ZPANRs can be scaled easily. Bandgap scaling in terms of ribbon width, length and antidot number was thoroughly analyzed for ZPANRs. In the end, a two-terminal device was constructed and transmission analysis was performed using the nonequilibrium Green's function (NEGF) methodology. A negative differential resistance (NDR) region appeared in the current–voltage characteristics of the ZPANRs, which paved a pathway for nano-device application.