Spontaneous magnetic moments in YBCO thin films

Abstract

We have observed spontaneous magnetic moments with random signs in c-axis oriented thin films of the high-Tc cuprate superconductor YBCO, imaged with a scanning SQUID microscope. These moments arise when the samples become superconducting, and appear to be associated with non-ferromagnetic defects in the films. In contrast with granular high-Tc samples, which also show spontaneous magnetization with random signs, these samples shield diamagnetically.

4 pages, 4 figures

References in corpus (3)

• Magnetic field of an in-plane vortex outside a layered superconductor
• Magnetic Impurities in d-wave Superconductors
• Spontaneous flux in a d-wave superconductor with time-reversal-symmetry-broken pairing state at {110} boundaries

Cited by in corpus (6)

• Andreev bound states in high-$T_c$ superconducting junctions
• d+is vs d+id' Time Reversal Symmetry Breaking States in Finite Size Systems
• Competing orders and the doping and momentum dependent quasiparticle excitations in cuprate superconductors
• Absence of broken time reversal symmetry beneath the surface of YBCO films
• Mesoscopic conductance fluctuations in YBa${}_2$Cu${}_3$O${}_{7-\delta }$ grain boundary Junction at low temperature
• Current in narrow channels of anisotropic superconductors