Low-Cost Trapped-Ion Quantum MVP

We here present an ultra-low-cost plan to create an MVP for a 4-qubit trapped-ion quantum computer.

Using the design and build details from the Innsbruck group's paper "Compact Ion-Trap Quantum Computing Demonstrator" (Pogorelov et al., PRX Quantum 2, 020343, 2021), we use \(^{40}\mathrm{Ca}^{+}\) ions as the species of choice; with the \(\lvert 1 \rangle\) state given by the \(\lvert 4S_{1/2}, m_J = -\tfrac{1}{2} \rangle\) Zeeman state and \(\lvert 3D_{5/2}, m_J = -\tfrac{1}{2} \rangle\) as the \(\lvert 0 \rangle\) state.

We make use of the standard commercial suppliers for the majority of parts, and cut costs where possible via 3D printing of specific components.

Lab Location

Techspace One, Sci-Tech Daresbury

Ground floor lab unit · Keckwick Lane, Daresbury, WA4 4AB

  • Class 2 lab space with 3-phase power, fume extraction, and external door access
  • On-site nitrogen, compressed air, and gas storage
  • 24/7 access
  • Located on the Sci-Tech Daresbury campus, adjacent to the STFC Daresbury Laboratory

Bill of Materials (BOM)

2026 component costs for a functional 4-qubit MVP, £108k across 89 components, based on actual supplier pricing. Only MVP-essential items are listed. View full spreadsheet →

Vacuum System

~£20k

  • 6-way CF cube chamber: Lesker CU6-0600
  • CF reducers, viewports (AR-coated fused silica), blanks, copper gaskets, feedthrough (Kurt J. Lesker)
  • Turbo pump (Pfeiffer HiPace 80) + scroll backing pump + ion pump (Agilent VacIon Plus 20)
  • All-metal valve, ion gauge + controller, bakeout heater kit
  • Resistive Ca oven (DIY, with Ca granules from Sigma-Aldrich)

Optics, Beam Delivery & Detection

~£17k

Control Electronics

~£12k

  • Kasli FPGA controller + ARTIQ: Sinara / M-Labs
  • Urukul 4-ch DDS x2, Zotino 32-ch DAC, HVAmp (Sinara ecosystem)
  • RF amplifiers for AOMs (Mini-Circuits ZHL) + trap RF amp (LZY-22+)
  • DIY helical resonator, clock distribution, oscilloscope, power supplies

Structural & Safety

~£7k

  • Optical table (1200x900 mm, pneumatic isolation): OptoSigma
  • Breadboards, posts, pedestal risers, Helmholtz coil pair (Thorlabs)
  • 3D-printed mounts, jigs, brackets (FDM/resin)
  • Laser goggles (OD5+ at 397/729 nm), interlocks, HV gloves, fire extinguisher, first aid

3D Printing Guide

  1. Pull free OQD design objects for enclosure/mount components.
  2. FDM/resin prints limited to simple brackets, jigs, coil formers, and cable mounts.
  3. No UHV-critical or precision parts printed in-house.

Print cost target: under £50.

Step-by-Step Assembly

Phase 1 · Weeks 1–4

Mechanical & Vacuum

  • Assemble mounts, base, and shielding frame.
  • Build chamber with CF hardware and trap drawer.
  • Bake out at 200–300°C for 48–72 h.
  • Pump to target: <10−10 mbar.

Phase 2 · Weeks 5–8

Lasers & Optics

  • Build and align laser rack with fiber delivery.
  • Lock lasers using PDH/grating feedback chain.
  • Align cooling beams and imaging path via high-NA objective.

Phase 3 · Weeks 9–10

Electronics & Control

  • Wire Sinara/ARTIQ stack and DDS cards.
  • Load gateware and configure timing/control software.

Phase 4 · Weeks 11–12+

Commissioning

  • Load ions (resistive oven + two-photon photoionisation).
  • Doppler cool and minimize micromotion.
  • Calibrate single-qubit and MS two-qubit gates.
  • Run Bell state, then optimize toward GHZ and fidelity.

Software Stack

Core Stack

  • ARTIQ
  • DAX / OQDAX
  • Sinara hardware ecosystem
  • OQD teaching demo references

First Program Goal

  • Load 4 ions
  • Perform cooling sequence
  • Execute Bell-state circuit
  • Measure and iterate calibration

Budget Snapshot

Hardware (BOM — MVP essentials only)

£108,188

Consumables & Tooling

~£500

Labour / Iterations

£40k–£75k

Total Realistic Budget: ~£200k