Superconductor-insulator transition in nanowires and nanowire arrays
  Superconducting nanowires are the dual elements to Josephson junctions, with quantum phase-slip processes replacing the tunneling of Cooper pairs. When the quantum phase-slip amplitude ES is much smaller than the inductive energy EL, the nanowire responds as a superconducting inductor. When the inductive energy is small, the response is capacitive. The crossover at low temperatures as a function of ES/EL is discussed and compared with earlier experimental results. For one-dimensional and two-dimensional arrays of nanowires quantum phase transitions are expected as a function of ES/EL. They can be tuned by a homogeneous magnetic frustration. 
Hans Mooij, Gerd Sch\"on, Alexander Shnirman, Tomoko Fuse, Hannes   Rotzinger, Kees Harmans and Ad Verbruggen
cond-mat.supr-con cond-mat.mes-hall