First-principles studies on electronic properties of Oligo-p-phenylene molecular device

The electronic properties of Oligo-p-phenylene molecular device are studied through density functional theory (DFT) in combination with non-equilibrium Green's function (NEGF). The electronic transport properties of Oligo-p-phenylene molecular device are investigated in terms of I-V characteristics, transmission spectrum and total density of states (TDOS). The TDOS gets modified with the number of phenyl units present in the device and also the applied bias voltage influence Oligo-p-phenylene molecular device. The density of charge along Oligo-p-phenylene molecular device is observed in both the conduction band and in the valence band upon increasing bias voltage. The transmission spectrum of Oligo-p-phenylene molecular device provides the insights on the transition of electrons across various energy intervals. The results of the present work clearly show that Oligo-p-phenylene molecular device can be utilized as negative differential resistance (NDR) device and its NDR property can be fine-tuned with the bias voltage and also by the number of phenyl units.