2001/08/21 by Nina Marković, N. Markovic, C. Christiansen +2 · 1 citation
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Surface and Thin Film Phenomena #Theoretical and Computational Physics #cond-mat.dis-nn #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.65.012501
4 pages text, 4 figures
arxiv created 2001/08/21 · openalex publication_date 2001/11/29 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The effect of an electric field on the conductance of ultrathin films of metals deposited on substrates coated with a thin layer of amorphous Ge was investigated. A contribution to the conductance modulation symmetric with respect to the polarity of the applied electric field was found in regimes in which there was no sign of glassy behavior. For films with thicknesses that put them on the insulating side of the superconductor-insulator transition, the conductance increased with electric field, whereas for films that were becoming superconducting it decreased. Application of magnetic fields to the latter, which reduce the transition temperature and ultimately quench superconductivity, changed the sign of the reponse of the conductance to electric field back to that found for insulators. We propose that this symmetric response to capacitive charging is a consequence of changes in the conductance of the a\ensuremath-Ge layer, and is not a fundamental property of the physics of the superconductor-insulator transition as previously suggested.