Macroscopic Quantum Tunneling in Josephson Junctions
1985Two companion 1985 papers (Devoret, Martinis & Clarke) reported the first clean observation of macroscopic quantum tunneling out of the zero-voltage state of a current-biased Josephson junction, and of quantized energy levels in that same state -- the first time quantum mechanical behavior (tunneling and discrete energy levels) was demonstrated in a macroscopic electrical circuit variable rather than a microscopic particle. Real theoretical precedent exists from 1981-84 (Leggett-style proposals that this should be observable, and studies of how dissipation affects it), confirmed via OpenAlex noise test -- not noise, a genuine multi-year lead-up. Basis for the 2025 Nobel Prize (Clarke, Devoret, Martinis) -- 2025 is the Nobel year, not the discovery year.
Discovery Velocity
Normalized OpenAlex paper velocity, one point per year.
Originators
- John Clarke
- Michel H. Devoret
- John M. Martinis
Landmark Paper
Checked 2026-08-30 — interim signal only, see docs/BASIC_ROADMAP.md Phase 10
Connections
- is precursor to Superconducting Qubitsbasis: reasoned
Nobel committee's own official scientific background (2025 Physics Prize, awarded to Devoret/Martinis/Clarke for this work): the 1985 experiments showed the circuit's energy is quantized into discrete levels "analogous to the orbitals of an atom" -- because the circuit behaves like an artificial atom, its two lowest energy levels can serve as a qubit. Martinis, a co-author on the 1985 papers, later led Google's superconducting-qubit program (Sycamore, Willow) built directly on this principle.