Evaluation of electronic and transport properties of a nano-scale device in the presence of electric field

The effect of external electric field (EF) in electronic properties of an organic semiconductor (OSE) molecule sandwiched between two ferromagnetic electrodes has been carried out. We adopt a modified Su–Schrieffer–Heeger (SSH) Hamiltonian for describing the isolated Pentathiophene molecule. The ground state of the molecule is obtained by Hellmann–Feynman theorem. Our calculation results show that by taking into account the presence of EF lattice distortion, electron density and HOMO–LUMO gap will be changed. Using Green’s function formalism we have also studied the effect of these changes on transport properties of molecule. Our results show that in the presence of EF current and TMR decrease, the negative differential resistance (NDR) occurs.