Hardware inventions · quantum · the qubit

TRANSMON

|0⟩|1⟩|2⟩ |3⟩ |4⟩ |5⟩ → continuum

A superconducting qubit is an anharmonic ladder. Drive it gently and it's a clean two-level system; drive it hard and population climbs the rungs, sheds a quantum at each gap, and finally ionizes out of the well. The question this repo asks: when energy leaks, is it lost — or is the leak the product?

// the real physics

A Josephson junction makes the ladder uneven

A transmon is a Josephson junction shunted by a large capacitor. The junction's nonlinearity warps the harmonic well so the energy gaps are not equal — the anharmonicity. That unevenness is the whole trick: tune your drive to the |0⟩↔|1⟩ gap and the |1⟩→|2⟩ transition is detuned away, so you get a clean qubit out of an infinite ladder.

E_J/E_C ≈ 50–100
the transmon regime
flattens charge dispersion → exponentially insensitive to charge noise.
ω₀₁/2π ≈ 4–6 GHz
qubit frequency
the |0⟩↔|1⟩ transition you drive and read.
α ≈ −E_C ≈ −200 MHz
anharmonicity
the gap shrinks each rung up — why the qubit is addressable.
DRAG
leakage suppression
shapes the pulse to kill the |1⟩→|2⟩ leak out of the computational subspace.
// the instrument · live

Climb the rungs, shed a quantum, ionize

Each gap crossing drives population up one rung and sheds a quantum — and because the ladder is anharmonic, each gap is smaller than the last. Push past |5⟩ and the population leaves the well entirely: transmon ionization, a real, studied effect (strong drive ejects the state into the continuum). Drive harder, climb faster. Then flip the fork.

|0⟩→|5⟩ ladder · shed quanta · 256 → 257 escapeopen full-screen ↗
// the fork · lost, or the product

The leak is the product

Every rung crossing sheds energy. In an isolated qubit that energy is simply gone — the populations no longer sum to one, conservation is broken inside the well. But couple a second mode to the climb and the leak has somewhere to land:

✗ OPEN — lost

Shed quanta fly off; Σp < 1. The well leaks energy to the continuum and there is no ledger that balances. Standard isolated-qubit decay.

✓ COLLECT — Patricia

A coupled resonator (Patricia) catches the shed quanta. Close the system at the larger boundary and conservation returns: qutrit + collector = 1. The leak becomes a harvested output.

⚠ the seam, kept visible

Ladder-climb and ionization are real transmon physics. That shed energy is genuinely lost in an isolated qubit. Collecting it requires a real coupled mode (the Patricia resonator) — physically coherent, and it's where conservation is restored. Whether the leak is a harvestable product or simply waste is the architectural claim to defend — not a settled result. The simulation shows the bookkeeping; the engineering is open.

// the read · −1 / 0 / +1

The same ternary, on the ladder

The rungs map onto the −1 / 0 / +1 field that runs through the wider work — shadow, witness, carrier:

|0⟩ · −1
shadow — ground, the floor of the well
|1⟩ · 0
witness — the working level, held
|2..5⟩ · +1
carrier — the climb itself, not a fixed level

The carrier is the climb, not a rung — the crossing count, the process. Above it all, the continuum: 256 → 257, escape.

// on emergence · evaluated honestly

No emergent behavior here — and that's fine

This repo was checked for emergent behavior (the bar that earns an artfully-crafted-intellect). It doesn't clear it: the ladder-climb is deterministic transmon physics, and the Patricia collector is a designed conservation closure, not self-organizing or adaptive dynamics. So no ACI was minted — the DLW tag is reserved for genuine emergence (as with the survival seed's Anabios), and stamping it here would cheapen it.

What this is: a faithful transmon instrument and a sharp architectural question. The honesty is the point.