Quantum tunneling theory of Cooper pairs as bosonic particles

• Main Authors: Edgar J. Patiño, Daniel Lozano-Gómez
• Format: Article
• Language: English
• Published: Nature Publishing Group 2021-04-01
• Series: Scientific Reports
• Online Access: https://doi.org/10.1038/s41598-021-88228-1

Abstract We propose a simple phenomenological theory for quantum tunneling of Cooper pairs, in superconductor/insulator/superconductor tunnel junctions, for a regime where the system can be modeled as bosonic particles. Indeed, provided there is an absence of quasiparticle excitations (fermions), our model reveals a rapid increase in tunneling current, around zero bias voltage, which rapidly saturates. This manifests as a zero bias conductance peak that strongly depends on the superconductors temperature in a non-monotonic way. This low energy tunneling of Cooper pairs could serve as an alternative explanation for a number of tunneling experiments where zero bias conductance peak has been observed.