2010/04/07 by Jacob Linder, Asle Sudbø, Takehito Yokoyama +2
Chemistry · Materials Science · Physics and Astronomy · #Amplitude #Chemistry #Coherence length #Condensed matter physics #Density of states #Electron #Inverse #Layer (electronics) #Magnetic and transport properties of perovskites and related materials #Pairing #Physics #Physics of Superconductivity and Magnetism #Polarization (electrochemistry) #Proximity effect (electron beam lithography) #Pseudogap #Quantum and electron transport phenomena #Quantum mechanics #Scattering #Spin polarization #Superconducting coherence length #Superconductivity #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.81.214504
published as Phys. Rev. B 81, 214504 (2010) · 14 pages, 12 figures. Submitted to Physical Review. Chosen as Editors' Suggestion
arxiv created 2010/04/07 · openalex publication_date 2010/06/03 · arxiv updated 2015/05/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the mutual proximity effect in a normal metal contacted to a superconductor through a magnetic interface. Analytical and self-consistent numerical results are presented, and we consider both the diffusive and ballistic regimes. We focus on the density of states in both the normal and superconducting region, and find that the presence of spin-dependent phase shifts occurring at the interface qualitatively modifies the density of states. In particular, we find that the proximity-induced pairing amplitudes in the normal metal region undergo a conversion at the Fermi level from pure even frequency to odd frequency. Above a critical value of the interface spin polarization (or, equivalently, for fixed interface spin polarization, above a critical interface resistance), only odd frequency correlations remain. This is accompanied by the replacement of the familiar proximity minigap or pseudogap in the normal layer by an enhancement of the density of states above its normal state value for energies near the chemical potential. The robustness of this effect toward inelastic scattering, impurity scattering, and the depletion of the superconducting order parameter close to the interface is investigated. We also study the inverse proximity effect in the diffusive limit. We find that the above-mentioned conversion persists also for thin superconducting layers comparable in size to the superconducting coherence length \ensuremathξS, as long as the inverse proximity effect is relatively weak. Concomitantly, we find a shift in the critical interface resistance where the pairing conversion occurs. Our findings suggest a robust and simple method for producing purely odd-frequency superconducting correlations, which can be tested experimentally.