Light-Driven Modulation of Electrical Current through DNA sequences: Engineering of a Molecular Optical Switch.

The design of a molecular switch that has bistable on/off states is of particular interest in molecular electronics. Motivated by experimental studies of molecular conductors, interplays of photons and electrons and their effects on electrical properties are studied theoretically. We have tried to design a molecular optical switch based on DNA sequences of the Hepatitis delta virus and Toxocara canis parasite. Electrical response of chains to the light irradiation examined to be optimized the function of a optical switch. The switch turns on when the amplitude of incident irradiation and its frequency approach to $0.3$ at the unit of $\frac{\hbar c}{ier_{0}}$ and $2~THz$, respectively. We can modulate the switching of the system via the simultaneous variation of effective factors and obtain different islands in parameter settings. The appearing of different islands in the parameter surface investigates the on/off states of electrical current which can be verified and estimated through the multifractal analysis.