Double-stranded DNA field effect transistor and logical cells

We consider a double-stranded DNA molecule connected to non-magnetic and magnetic (nickel (Ni) and iron (Fe)) leads and study its spintronic properties using tight binding non-equilibrium Green function method. By considering the combination of the spin-orbit coupling, the environment-induced dephasing, and the helical symmetry, it is shown that although the hopping parameter of spin up electrons is higher than spin down electrons for both Ni and Fe leads, the spin up (spin down) current is significantly higher than spin down (spin up) current when the lead is Ni (Fe) and for non-magnetic leads the difference is not high with respect to magnetic leads, i.e., there should be a matching process rule between leads and dsDNA. Also, we show that by applying an AC electric (gating) field perpendicular to helix-axis, the spin current is approximately zero at half period and will be maximized for specific gate voltage at other half period and therefore dsDNA habits as a field effect transistor (FET). It is found that there are both p-channel and n-channel FET and the logical cell can be designed theoretically. We think that the results of present paper could motivate further experimental studies on DNA spintronics.