Resistance-shunted Josephson junctions are studied theoretically based on a tight-binding model. In addition to the effective bandwidth 2ℏΔeff, this multi-level system genuinely has a novel crossover at lower energy KℏΔeff below which the density of states becomes strongly degenerate, where K is a dimensionless damping strength. The optical responses take nearly Lorentzian forms with a width of the order of KℏΔ. The non-linear I-V characteristics is also discussed.
- Coulomb blockade
- Josephson junction
- Superconductor-insulator transition
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering