RCSJ Washboard Lab

Phase particle on a tilted washboard: bias near Ic, trigger → slip ~2π → voltage pulse with area Φ₀. Damping (βC) decides pulse-and-recover vs latch.

0.85
Regime
overdamped
φ advance
0
Slips
0
∫V dt
0
After event
ready
Washboard U(φ) — tilt from bias · particle = phase
Voltage V(t) — shaded area ≈ n·Φ₀ for completed slips

RSFQ gates want overdamped: one click, recover to V≈0. I/O latching often uses underdamped: particle keeps running (latched V) until reset. Teaching cartoon — not a full RCSJ ODE solver.