2012-01-25# String theory is used to model superconductivity in nanowires |

Gauge/gravity theory has been used to advance the theory of superconductivity in thin wires. The work is done by

Sergei Khlebnikov of Purdue University. In this new theoretical approach the number of channels of the gauge theory is analogous to the number of the active transverse channels in the nanowire. In the gravity phase, the behavior is modeled by a system of D3 and D5 branes which intersect over a line. Both the transition due to an initial winding of the order parameter (as appropriate for a superconducting ring) and the transition at fixed current are analyzed. It is found that they are substantially different. In the first case the supercurrent is metastable and becomes classically unstable at some maximal winding. In the second case there is a continuous phase transition in the universality class of the dissipative XY model. The results of the nanowire superstring theory match recent experiments on standard deviation of the switching current in nanowires. The work appeared on the

ArXive (http://lanl.arxiv.org/abs/1201.5103).

## String theory is used to model superconductivity in nanowires