Tunneling Effects in DNA bases Adenine and Guanine

Molecular electronics has been the centre stage of research recently. Much interest has been shown by scientists in exploring the electrical and electronic properties of DNA. In this paper DNA bases Adenine and Guanine are being explored for its use as tunneling device. The molecules are applied variable bias voltage ranging from –5V to +5V to observe the flow of current using two-probe setup of Virtual Nanolab. The current–voltage characteristics obtained resemble typical tunnel diode characteristic with display of resonant tunneling phenomenon in the molecule. The two molecules Adenine and Guanine exhibit Negative Differential Resistance with a considerably large Peak to Valley Current Ratio (PVR). The observations suggest that the two molecules may be used in molecular resonant devices. The NDR characteristic suggests useful utilization of the proposed device in nanoscale digital circuits. Also the large value of PVR supports the use of Adenine in power saving highdensity integrated circuits.