TODO: curves showing the effect.
The effect is likely mentioned in Leitner's video at: https://www.youtube.com/watch?v=BFdq6IecUJc&t=2290s
Bibliography:
- https://www.youtube.com/watch?v=cnZ6exn2CkE "Superconductivity: Professor Brian Josephson". Several random excerpts from Cambridge people talking about the Josephson effect