NAND/AND/NOT logic gates response in series of mesoscopic quantum rings.

There is a special class of logic gates, called universal gates, any one of which is sufficient to express any desired computation. The NAND gate is truly global, given that it is already known, each Boolean function can be represented in a circuit that contains only NOT and AND gates, it is sufficient to show that these gates can be defined from the NAND gate. The effect of Rashba spin-orbit interaction (SOI) on the gate response and spin current density in a series of non-interacting one-dimensional rings connected to some leads is studied theoretically within the waveguide theory. The gates response and spin current density are computed in geometry of the system containing two terminal double quantum rings. Also, the presence and absence of Rashba SOI are treated as the two inputs of the AND/NAND/NOT gates. Furthermore, simulation of the device performance demonstrates that vital improvement toward spintronic applications can be achieved by optimizing device parameters such as magnetic flux and Rashba coefficient. [ABSTRACT FROM AUTHOR]