Signature of Cooper Pairs in the Non-Superconducting Phases of Amorphous Superconducting Tantalum Films

Abstract

We have studied the magnetic field or disorder induced insulating and metallic phases in amorphous Ta superconducting thin films. The evolution of the nonlinear transport in the insulating phase exhibits a non-monotonic behavior as the magnetic field is increased. We suggest that this observation could be an evidence of the presence of localized Cooper pairs in the insulating phase. As the metallic phase intervenes the superconducting and insulating states in Ta films, this result further reveals that Cooper pairs also exist in the metallic ground state.

References in corpus (8)

• Localization of preformed Cooper-pairs in disordered superconductors
• Nature of the superconductor-insulator transition in disordered superconductors
• Theory of quantum metal to superconductor transitions in highly conducting systems
• Magnetically Induced Metallic Phase in Superconducting Tantalum Films
• Quantum Metallicity on the High-Field Side of the Superconductor-Insulator Transition
• Jumps in current-voltage characteristics in disordered films
• Non-thermal origin of nonlinear transport across magnetically induced superconductor-metal-insulator transition
• Evidence of spatial inhomogeneity near the onset of magnetically induced insulating state in superconducting thin films