An odd-frequency Cooper pair around a magnetic impurity

Abstract

The Yu-Shiba-Rusinov (YSR) state appears as a bound state of a quasiparticle at a magnetic atom embedded in a superconductor. We discuss why the YSR state has energy below the superconducting gap and why the pair potential changes the sign at the magnetic atom. Although a magnetic atom in a superconductor has been considered as a pair breaker since 1960s, we propose an alternative physical picture to explain these reasons. We show that a magnetic atom converts a spin-singlet s-wave Cooper pair into an odd-frequency pair rather than breaking it. The odd-frequency pairing correlations always coexist with the quasiparticle states below the gap. The YSR state is an example of such a subgap quasiparticle state. The paramagnetic property of an odd-frequency pair explains the sign change of the pair potential at a magnetic atom and the decrease of superconducting transition temperature in the presence of many magnetic impurities.

12 pages, 4 figures

References in corpus (11)

• Observation of Majorana Fermions in Ferromagnetic Atomic Chains on a Superconductor
• Bogoliubov Fermi surfaces in superconductors with broken time-reversal symmetry
• Majorana Fermions and Odd-frequency Cooper Pairs in a Nano Wire
• Odd-frequency superconducting states with different types of Meissner response: Problem of coexistence
• Theory of pairing symmetry inside the Abrikosov vortex core
• Model for Vortex-core tunneling spectroscopy of chiral p-wave superconductors via odd-frequency pairing states
• Effects of surface roughness on the paramagnetic response of small unconventional superconductors
• Odd-frequency pair in topological superconductivity of 1D magnetic chain
• Consequences of bulk odd-frequency superconducting states for the classification of Cooper pairs
• Odd-frequency pairing effect on the superfluid density and the Pauli spin susceptibility in spatially nonuniform spin-singlet superconductors
• Quasiparticle on Bogoliubov Fermi Surface and Odd-Frequency Cooper Pair

Cited by in corpus (7)

• Stealth Majorana Zero Mode in a Trilayer Heterostructure MnTe/Bi2Te3/Fe(Te,Se)
• Discontinuous Transition to Superconducting Phase
• Bound states around impurities in a superconducting bilayer
• Spin Susceptibility of a J=3/2 Superconductor
• Predicting topological invariants and unconventional superconducting pairing from density of states and machine learning
• Yu-Shiba-Rusinov bound states boost odd-frequency superconductivity
• Fulde-Ferrell-Larkin-Ovchinnikov state in a superconducting thin film attached to a ferromagnetic cluster