Josephson (Φ, Q) symplectic phase space: [Φ, Q] = iℏ; ΔΦ·ΔQ ≥ ℏ/2 symplectic-capacity bound

Superconducting-circuit symplectic phase space. Setup: a single superconducting-circuit node has canonical coordinate Φ (flux) and conjugate momentum Q (charge) with Poisson bracket {Φ, Q} = 1 (classical) or commutator [Φ̂, Q̂] = iℏ…