A proximity induced pseudogap - evidence for preformed pairs

Abstract

The temperature evolution of the proximity effect in Au/La${}_{2-x}$Sr${}_x$CuO${}_4$ and La${}_{1.55}$Sr${}_{0.45}$CuO${}_4$/La${}_{2-x}$Sr${}_x$CuO${}_4$ bilayers was investigated using scanning tunneling microscopy. Proximity induced gaps, centered at the chemical potential, were found to persist above the superconducting transition temperature, $T_c$, and up to nearly the pseudogap crossover temperature in both systems. Such independence of the spectra on the details of the normal metal cap layer is incompatible with a density-wave order origin. However, our results can be accounted for by a penetration of incoherent Cooper pairs into the normal metal above $T_c$.

4 pages, 3 figures

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Cited by in corpus (12)

• Fractal superconductivity near localization threshold
• Anomalous Enhancement of the Superconducting Transition Temperature in Electron-Doped Cuprate Heterostructures
• Boson-Fermion Duality and Metastability in Cuprate Superconductors
• Hybrid high-temperature superconductor-semiconductor tunnel diode
• Proximity induced pseudogap in mesoscopic superconductor/normal-metal bilayers
• Flow equation approach to the linear response theory of superconductors
• Mixed temperature-dependent order parameters in the extended Hubbard model
• Unconventional particle-hole mixing in the systems with strong superconducting fluctuations
• Nonequilibrium probe of paired electron pockets in the underdoped cuprates
• Mott Criticality as the Confinement Transition of a Pseudogap-Mott Metal
• Quasiparticle states driven by a scattering on the preformed electron pairs
• Fluctuation conductivity due to the preformed local pairs