Tempo

Raveh Neeman

doi:10.5281/zenodo.22674814

IonQ · trapped ions · DEMONSTRATED (25 Sep 2025) · 64 physical qubits · access: lab (development system); the 100-qubit product sold to KISTI, delivery not dated

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: barium ions (IonQ: "a barium system"); isotope and qubit levels not stated for Tempo

gate mechanism: laser Molmer-Sorensen, AOD-steered beams; no gate time or per-pair fidelity published for the development system

connectivity: all-to-all in a single ion chain (development system); the product is listed as "many-to-many"

control: room-temperature electronics + free-space AOM/AOD

control placement: room-temp + free-space optics

readout: fluorescence

gate evidence: no published figure

decoder mode: offline — syndromes decoded after the run

flags: no published error rates

Technologies by layer — the machine's cell per layer

1 Qubit carrier	Trapped atomic ion · primary ▦ 🔎 barium ions (species change from Forte's Yb; species not stated on IonQ page); IonQ page: "target qubits" 100, #AQ 64
2 Encoding	Hyperfine / clock-state qubit · primary ◌ 🔎 hyperfine qubit (species not stated on the IonQ page)
3 Gate mechanism	Mølmer–Sørensen / light-shift laser gate · primary ▦ ✅ laser Mølmer–Sørensen; 99.9% target fidelity (IonQ page); no published gate time or per-pair fidelity for the 100-ion chain
4 Connectivity / transport	Ion-chain motional bus (all-to-all in chain) · primary ▦ 🔎 single long chain, all-to-all claimed; 100 target qubits (degree 99); a secondary source claims 256 physical — conflict
5 Control	Free-space laser addressing of ions (AOM/AOD beams) · primary ▦ 🔎 room-temperature electronics + free-space AOM/AOD laser addressing
6 Readout	Fluorescence state detection (ions, defects) · primary ◌ 🔎 fluorescence
7 Code	— none — nothing in this layer ◌ 🔎 no code on Tempo (see ionq-ba133-qldpc-testbed)
8 Decoder	— none — nothing in this layer ◌ 🔎 none
9 Interconnect	— none — nothing in this layer ◌ 🔎 monolithic single module, no interconnect
10 Manufacturing	Ion-trap fabrication (surface-electrode chips; machined 3D blade traps) · primary ◌ 🔎 surface-electrode ion trap; no Tempo-specific fab source

evidence: ✅ 1 / 10