2006/10/02 by J. E. Sonier, Sonier, J. E., F. D. Callaghan +23
Physics and Astronomy · #FOS: Physical sciences #Superconductivity (cond-mat.supr-con) #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0610051
4 pages, 3 figures, submitted to PRL
arxiv created 2006/10/02 · arxiv updated 2009/12/01
Spin-glass magnetism confined to individual weakly interacting vortices is detected in two different families of high-transition-temperature (Tc) superconductors, but only in samples on the low-doping side of the low-temperature normal state metal-to-insulator crossover (MIC). Our findings unravel the mystery of the MIC, but more importantly identify the true location of the field-induced quantum phase transition (QPT) in the superconducting state. The non-uniform appearance of magnetism in the vortex state favours a surprisingly exotic phase diagram, in which spatially inhomogeneous competing order is stabilized at the QPT, and an `avoided' quantum critical point (QCP) is realized at zero magnetic field.