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Negative differential resistance (NDR) in two dimensional materials has been the subject of strong interest for ultra-low power nanoelectronic applications. Here, we report NDR characteristics of silicene superlattice (SL) at low bias voltages. Transport process manipulated by miniband regime for low bias region and Wannier-Stark (WS) ladders regime with multi-peak NDR for higher bias windows. Local tunneling peaks rise from hybridization of Wannier-Stark rungs in certain bias voltages. The bias position of WS states crossings down shifted with increasing device dimension leading to red shifted NDR window and increases peak to valley ratio (PVR) values. The multiple NDR windows are represented by changing the size and the number of well/barriers in silicene SL. Maximum PVR of 8 obtained for device with low height barriers. Multi-peak NDR with same PVR values in very low bias regime can find key applications in multi-valued memories with low static power dissipation.

Partially fluorinated graphene films were created by chemical functionalization of graphene layers in an aqueous solution of hydrofluoric acid. The formation of graphene islands or graphene quantum dots (GQDs) and a fluorinated graphene network is demonstrated in such films. Negative differential resistance (NDR) resulting from the formation of the potential barrier system in the films was observed for different fluorination degrees of suspension. The origin of the NDR varies with an increase in the fluorination degree of the suspension. Numerical calculations were performed to elucidate the tunneling between adjacent energy levels and creation of NDR. It was found that in the case of films with smaller flake and smaller GQD sizes, multi-peak NDR appears in the I–V curve. We predict that the NDR peak position shifts towards lower voltage with a decrease in the GQD size. Surprisingly, we observed a negative step-like valley for positive biases in the I-V curve of samples. Our findings with detailed analysi...

Here, we study the negative differential resistance (NDR) of Dirac electrons in biased planar graphene superlattice (PGSL) and investigate the transport characteristics by adopted transfer matrix method within Landauer-Buttiker formalism. Our model device is based on one-dimensional Kronig–Penney type electrostatic potential in monolayer graphene deposited on a substrate, where the bias voltage is applied by two electrodes in the left and right. At Low bias voltages, we found that NDR appears due to breaking of minibands to Wannier-Stark ladders (WSLs). At the critical bias voltage, delocalization appeared by WS states leads to tunneling peak current in current-voltage (I-V) characteristics. With increasing bias voltage, crossing of rungs from various WSL results in multi-peak NDR. The results demonstrate that the structure parameters like barrier/well thickness and barrier height have remarkable effect on I-V characteristics of PGSL. In addition, Dirac gap enhances peak to valley (PVR) value due to suppr...