!

Quick Verdict

IQM Garnet uses Superconducting while Xanadu Borealis uses Photonic technology. Xanadu Borealis offers more physical qubits (216 qubits).

Specification Comparison

Metric IQM Garnet Xanadu Borealis
Physical Qubits 20 216 ✓
Technology Superconducting Photonic
2Q Gate Fidelity 99.50% ✓
1Q Gate Fidelity 99.94% ✓
Readout Fidelity 98.50% ✓ 98.00%
Quantum Volume 128 ✓
CLOPS 5,000 ✓
T1 (Relaxation) 150 µs ✓
T2 (Dephasing) 100 µs ✓
1Q Gate Time 20 ns ✓
2Q Gate Time 120 ns ✓
Connectivity Custom (deg 4) Linear (deg 2)
Max Circuit Depth 1,000 ✓ 10
Max Shots 100,000 100,000
Dynamic Circuits No No
Error Mitigation Available No
Cloud Platforms 2 platforms 2 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: IQM Garnet: $1.75 vs Xanadu Borealis: $0.5000

Superconducting IQM Garnet

Platform Price Status
Best Amazon Braket
$0.001450/shot Available
qBraid
$0.001450/shot Available

Photonic Xanadu Borealis

Platform Price Status
Best Xanadu Cloud
$0.5000/task Available
qBraid
$0.5000/task Available

Superconducting vs Photonic: Technology Tradeoffs

Superconducting (used by IQM Garnet)
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 →
Photonic (used by Xanadu Borealis)
Advantage
Operates at room temperature (no cryogenics required), photons travel at the speed of light with minimal decoherence, and photonic hardware is compatible with existing fiber-optic telecommunications infrastructure for quantum networking.
Challenge
Deterministic photon-photon interactions are extremely difficult to engineer, making universal fault-tolerant quantum computation challenging. High photon loss rates and detector inefficiencies limit circuit depth. Current GBS machines are specialized rather than general-purpose.
Gate Speed
Picoseconds for passive operations; detector timing ~ns
Fidelity
Variable; loss-dominated; ~98% for single-photon detectors
Learn more →

Use Case Recommendations

Quantum Chemistry IQM Garnet

Higher 2Q gate fidelity (99.50%) means fewer errors in VQE/UCCSD circuits.

Large-scale Optimization Xanadu Borealis

More qubits (216 qubits) allows encoding larger problem instances.

Frequently Asked Questions

What is the difference between IQM Garnet and Xanadu Borealis?

IQM Garnet uses Superconducting while Xanadu Borealis uses Photonic technology. Xanadu Borealis offers more physical qubits (216 qubits). These QPUs use fundamentally different qubit technologies: Superconducting vs Photonic.

Which is better for quantum chemistry, IQM Garnet or Xanadu Borealis?

For quantum chemistry, gate fidelity is the most critical metric. Compare the 2Q gate fidelity figures in the spec table above to determine which QPU is better suited for your chemistry workload.

How do the prices compare between IQM Garnet and Xanadu Borealis?

IQM Garnet is available from $0.001450/shot on Amazon Braket. Xanadu Borealis is available from $0.5000/task on Xanadu Cloud. 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, IQM Garnet or Xanadu Borealis?

IQM Garnet uses Custom connectivity (degree 4) while Xanadu Borealis uses Linear connectivity (degree 2).

What are the coherence times for IQM Garnet vs Xanadu Borealis?

IQM Garnet: T1=150 µs, T2=100 µs.