Stillwater · 32-qubit trapped-ion processor
Quell is a quantum lab in Ghent. We hold a chain of calcium ions in a vacuum colder than deep space and compute with them, one laser pulse at a time. Researchers book the machine by the shot or by the hour.
01 — The machine
Stillwater has no chip. The qubits are atoms, identical by nature, and the wiring is light. Three things happen to them, again and again, thousands of times a second.
Thirty-two calcium ions float in a line 180 µm long, pinned by radio-frequency fields inside a cryogenic vacuum. Nothing touches them. They repel each other into perfect spacing and wait.
A 729 nm laser, narrower than the gap between ions, is swept along the chain by acousto-optic deflectors. Each pulse rotates exactly one qubit; pairs are entangled through their shared motion.
At the end of a circuit a 397 nm pulse makes every ion in state zero fluoresce. A cooled camera counts the photons. An ion that stays dark is a one. The answer is a row of lights.
02 — Live from Trap 03
Every job carries the calibration it ran under. This is the same console our physicists watch, with customer names shown by permission.
| Job | Circuit | State | Est. |
|---|---|---|---|
| QL-2210 | Hubbard model, 4×4 lattice | running | 00:14:07 |
| QL-2211 | Catalyst ground state, VQE | queued | 00:22:00 |
| QL-2212 | Error-correction cycle, [[7,1,3]] | queued | 00:09:30 |
| QL-2213 | Portfolio QAOA, 24 assets | queued | 00:31:15 |
| QL-2214 | Randomised benchmarking | held | 00:06:00 |
| Parameter | Value | Status |
|---|---|---|
| Carrier frequency, 729 nm | 411 042 129.7 MHz | locked |
| Beam pointing drift | 0.08 µm / h | nominal |
| Axial mode, COM | 1.212 MHz | nominal |
| Ion 19 · Rabi rate | −0.6 % from target | retuning |
| Magnetic field | 4.115 G ± 0.2 mG | nominal |
03 — One shot
Doppler and sideband cooling bring the chain to its motional ground state — colder than anything in the room by a factor of a billion.
Optical pumping sets every ion to zero. The register is blank and identical, every time.
The beam walks the chain: single-qubit rotations and Mølmer–Sørensen entangling gates, compiled to the native pulse set.
Fluorescence imaging. 32 bits leave the vacuum, and the chain is recooled for the next shot.
≈ 12.4 ms per shot · 80 shots a second · the chain is never reloaded unless an ion is lost
04 — Access
Three ways in, from a single API call to a desk beside the vacuum chamber. Academic groups pay half.