One-Dimensional Mott Insulator Formed by Quantum Vortices in Josephson Junction Arrays

Abstract
The quantum transport of vortices in very long and narrow arrays of small Josephson junctions has been studied experimentally. The chemical potential of the system can be changed by an external magnetic field. When the vortex density is commensurate with the one-dimensional junction lattice, the vortex mobility vanishes for a finite window of the magnetic field. The localization of the vortices is due to the forming of a one-dimensional Mott insulator.