Investigating magnetoresistance properties on a periodic poly(dA)-poly(dT) DNA structure

Magnetoresistance has been calculated for a range of magnetic fields. The calculation has been carried out using a periodic DNA structure. The magnetic field affects electron hopping constants in a tight-binding Hamiltonian regime through the Peierls phase. On the other hand, the internal electric field, as a result of the voltage difference across the molecule structure, affects the magnitude of electron hopping parameters. Green's function method has been employed in computing the electron transmission probabilities. Then, the Landauer-Buttiker formula is used in computing currents at a certain voltage. The magnetoresistance was observed oscillating as the magnetic field increased, just like the current. At several voltages, the magnetoresistance changes sign with the change in the magnetic field.