Quoll / QB-QDK 2.0

Raveh Neeman

doi:10.5281/zenodo.22674814

Quantum Brilliance · defect spins · DEPLOYED (2 Sep 2025 announcement; the cited page dates the ORNL QDK 2.0 procurement to 2024) · 6 physical qubits · access: on-prem sold

architecture: Colour-centre spins — network nodes (NV/SiV/T) · Open on the map

Register profile — the machine's variant of its architecture

qubit type: NV centre (electron spin + nearby C-13/N-14 nuclear spins) in synthetic diamond

gate mechanism: microwave ESR rotations + hyperfine-conditional nuclear gates; <0.1% error on NV electron+nuclear registers is the platform-level figure

connectivity: local register only (dipolar/hyperfine); no inter-NV entangling link in the product

control: room temperature: microwave drive + green-laser initialisation + optical readout; no cryogenics, no vacuum; 19-inch rack-mount accelerator node

control placement: room temperature, optical

readout: optical fluorescence spin readout

gate evidence: no published figure

flags: no published error rates

Technologies by layer — the machine's cell per layer

1 Qubit carrier	Colour-centre / defect spin (NV, SiV, SnV, T centre) · primary ▨ 🔎 NV centre (electron spin + nearby C-13/N-14 nuclear spins) in synthetic diamond; 2 qubits per QPU, 3 QPUs = 6 qubits (ORNL, 2 Sep 2025)
2 Encoding	Single-spin (Loss–DiVincenzo) / nuclear-spin encoding · primary ◌ 🔎 bare NV electron and nuclear spin-1/2; no machine-specific encoding source
3 Gate mechanism	Microwave / optical spin gates (defect centres, 1Q spins) · primary ▨ ✅ microwave ESR rotations + hyperfine-conditional nuclear gates; <0.1% error on NV registers is a platform figure (Fujitsu/QuTech); no QB product gate fidelity published
4 Connectivity / transport	Static nearest-neighbour lattice · primary ▨ 🔎 local register only (dipolar/hyperfine); no inter-NV entangling link in the product
5 Control	Baseband electrical control (spins, Majorana) · alternate ▨ 🔎 path-assigned ct_base (gate voltage pulses) does not describe NV control; actual control is room-temperature microwave + optical — (Atlas gap: ∅G-nvroom) · primary ▨ ✅ room-temperature microwave drive + green-laser initialisation + optical readout; no cryogenics, no vacuum; 19-inch rack-mount accelerator node
6 Readout	Fluorescence state detection (ions, defects) · primary ◌ 🔎 optical fluorescence spin readout at room temperature; no readout fidelity published
7 Code	— none — nothing in this layer ▨ 🔎 no code; small room-temperature QPUs
8 Decoder	— none — nothing in this layer ▨ 🔎 no decoder
9 Interconnect	— none — nothing in this layer ▨ 🔎 no inter-module link; scaling model is parallel independent QPUs (ORNL cluster of 3), which is not an interconnect
10 Manufacturing	Diamond growth / implantation (NV, SiV, SnV) · primary ▨ ✅ Quantum Diamond Foundry, Melbourne (2025); imec partnership; deterministic NV placement to ±1 nm at ~5–10 nm spacing, early success ~34%

evidence: ✅ 3 / 11