Innsbruck trapped-ion analog quantum simulator (up to 51 ions)

Raveh Neeman

doi:10.5281/zenodo.22674814

IQOQI Innsbruck (Austrian Academy of Sciences) with the University of Innsbruck (M. Joshi, C. Roos)

Innsbruck trapped-ion analog quantum simulator (up to 51 ions)

IQOQI Innsbruck (Austrian Academy of Sciences) with the University of Innsbruck (M. Joshi, C. Roos) · trapped ions · DEMONSTRATED (Aug 2026 (PRX 16, 031037; arXiv Nov 2025)) · 51 physical qubits · access: lab-only

architecture: Trapped ions — linear Paul trap with individual laser addressing · Open on the map

Register profile — the machine's variant of its architecture

qubit type: optical qubit (40Ca+ S1/2–D5/2 Zeeman sublevels, 729 nm)

gate mechanism: bichromatic laser-driven long-range Ising / XY spin-spin coupling - an analog simulator, not a gate-model machine

connectivity: linear Coulomb chain, long-range coupling over all ions, no transport

control: global bichromatic laser beam plus a steerable single-ion addressing beam

control placement: room-temp + free-space optics

readout: spatially resolved fluorescence

gate evidence: no published figure

flags: analogue operation only

Technologies by layer — the machine's cell per layer

1 Qubit carrier	Trapped atomic ion · primary ▤ §III; App. B (Experimental platform) ✅ linear strings of up to 51 40Ca+ ions in a linear RF trap
2 Encoding	Optical narrow-line qubit (ion S–D, atom clock) · primary ▤ App. B1 (Engineered many-body interactions) ✅ optical qubit: Zeeman sublevels S1/2 m=+1/2 and D5/2 m=+5/2, 729 nm quadrupole transition
3 Gate mechanism	— (Atlas gap: ∅G-isinganalog) · primary ▤ App. B1, Eqs. (B1)-(B3) ✅ analog long-range Ising / XY interaction from a bichromatic beam coupling all transverse modes; no gates
4 Connectivity / transport	— (Atlas gap: ∅G-crystal) · primary ▤ App. B1 ✅ static linear Coulomb chain, long-range (J0 = 185 rad/s, alpha = 0.97 at 51 ions), no transport
5 Control	Free-space laser addressing of ions (AOM/AOD beams) · primary ▤ App. B2 (Local control) ✅ global bichromatic beam plus a strongly focused steerable single-ion beam
6 Readout	Fluorescence state detection (ions, defects) · primary ▤ §III; App. B2 ✅ spatially resolved fluorescence detection
7 Code	— none — nothing in this layer ▤ 🔎 no QEC code (analog simulator)
8 Decoder	— none — nothing in this layer ▤ 🔎 no decoder (analog simulator)
9 Interconnect	— none — nothing in this layer ◌ 🔎 single trap, no interconnect
10 Manufacturing	Ion-trap fabrication (surface-electrode chips; machined 3D blade traps) · primary ▤ App. B (Experimental platform) ✅ linear radiofrequency ion trap

evidence: ✅ 7 / 10