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Quick Verdict

Google Willow uses Superconducting while Quantinuum H1-1 uses Trapped Ion technology. Both QPUs have comparable 2Q gate fidelity (~99.88%). Google Willow offers more physical qubits (105 qubits). Quantinuum H1-1's all-to-all connectivity eliminates SWAP overhead in circuit compilation.

Specification Comparison

Metric Google Willow Quantinuum H1-1
Physical Qubits 105 ✓ 20
Technology Superconducting Trapped Ion
2Q Gate Fidelity 99.88% ✓ 99.80%
1Q Gate Fidelity 99.97% 99.99% ✓
Readout Fidelity 99.90% 99.93% ✓
Quantum Volume 524,288 ✓
CLOPS 100,000 ✓ 40
T1 (Relaxation) 100 µs 5000 ms ✓
T2 (Dephasing) 80 µs 30 ms ✓
1Q Gate Time 25 ns ✓ 10 µs
2Q Gate Time 68 ns ✓ 1000 µs
Connectivity Grid (deg 4) All-to-All (deg 19)
Max Circuit Depth 1,000 1,000
Max Shots 1,000,000 ✓ 10,000
Dynamic Circuits No Yes
Error Mitigation Available Available
Cloud Platforms 0 platforms 3 platforms

Green bold values with a checkmark indicate the better result for each metric.

Pricing Comparison

Example: 10-qubit, 50-depth circuit, 1,000 shots — estimated cost on cheapest platform: Google Willow: N/A vs Quantinuum H1-1: $8,040.00

Superconducting Google Willow

No cloud access data available.

Trapped Ion Quantinuum H1-1

Platform Price Status
Best Azure Quantum
$120.00/HQC Available
Strangeworks
$135.00/HQC Available
qBraid
$120.00/HQC Available

Superconducting vs Trapped Ion: Technology Tradeoffs

Superconducting (used by Google Willow)
Advantage
Fast gate speeds (tens to hundreds of nanoseconds), mature fabrication technology using standard semiconductor processes, and strong industry investment make this the most commercially advanced platform.
Challenge
Requires dilution refrigerators operating near absolute zero (~15 mK), leading to large physical footprints and high infrastructure costs. Qubits are sensitive to noise, limiting coherence times to microseconds-to-milliseconds range.
Gate Speed
10–700 ns per gate
Fidelity
99.5–99.9% for 2-qubit gates
Learn more →
Trapped Ion (used by Quantinuum H1-1)
Advantage
Exceptional gate fidelities (99.9%+), long coherence times (seconds to hours), and native all-to-all qubit connectivity eliminate the need for SWAP routing that limits other architectures.
Challenge
Gate operations are slow (microseconds to milliseconds), limiting circuit throughput. Scaling to many ions in a single trap is difficult due to spectral crowding; modular trap architectures are being developed to address this.
Gate Speed
1 µs – 1 ms per gate
Fidelity
99.7–99.99% for 2-qubit gates
Learn more →

Use Case Recommendations

Quantum Chemistry Google Willow

Higher 2Q gate fidelity (99.88%) means fewer errors in VQE/UCCSD circuits.

Optimization (QAOA) Quantinuum H1-1

All-to-all connectivity maps optimization problems directly without SWAP overhead.

Error Correction Research Quantinuum H1-1

Supports dynamic circuits and mid-circuit measurement required for active error correction.

Frequently Asked Questions

What is the difference between Google Willow and Quantinuum H1-1?

Google Willow uses Superconducting while Quantinuum H1-1 uses Trapped Ion technology. Both QPUs have comparable 2Q gate fidelity (~99.88%). Google Willow offers more physical qubits (105 qubits). Quantinuum H1-1's all-to-all connectivity eliminates SWAP overhead in circuit compilation. These QPUs use fundamentally different qubit technologies: Superconducting vs Trapped Ion.

Which is better for quantum chemistry, Google Willow or Quantinuum H1-1?

For quantum chemistry simulations (VQE, UCCSD), Google Willow is preferred due to its higher 2Q gate fidelity (99.88% vs 99.80%). Higher gate fidelity directly reduces circuit error rates in chemistry algorithms.

How do the prices compare between Google Willow and Quantinuum H1-1?

Google Willow is available from no public cloud access. Quantinuum H1-1 is available from $120.00/HQC on Azure Quantum. Note that pricing models differ — per-shot pricing is directly comparable while AQT and HQC models depend on circuit structure.

Which QPU has better connectivity, Google Willow or Quantinuum H1-1?

Quantinuum H1-1 offers all-to-all connectivity, meaning any qubit can directly interact with any other. This eliminates the need for SWAP gates during compilation. Google Willow uses Grid connectivity.

What are the coherence times for Google Willow vs Quantinuum H1-1?

Google Willow: T1=100 µs, T2=80 µs. Quantinuum H1-1: T1=5000 ms, T2=30 ms. Quantinuum H1-1 has longer coherence times, which generally allows for deeper circuits before errors accumulate.