QC logical
Shielding
Passive Decoherence-Free Subspaces — IBM Heron R2
A unified system for passive preservation of quantum information. Empirically validated on commercial superconducting hardware. 95.2% average Bell-state fidelity across 57,344 shots, using 1D Z6 alternating parity invariants for topology-aware encoding.
Topology-Aware Encoding
Initializes linear chain into alternating invariant. Entanglement via nearest-neighbor CX only, ensuring heavy-hex compliance without routing.
Ground-State Bias Preservation
Maps data to maximize |0⟩ population. Thermal relaxation actively preserves baseline, reversing typical decoherence.
Parity Compression
Validates state via linear cascade, compressing global parity to single anchor qubit.
Live Results — IBM Heron R2
Raw measurements, no error mitigation. Testbed details in data repository.
| Run | Time UTC | c00 | c11 | Fidelity |
|---|---|---|---|---|
| 1 | 02:06:10 | 4736 | 3328 | 98.44% |
| 2 | 02:06:25 | 3968 | 3584 | 92.19% |
| 3 | 02:06:31 | 3712 | 4160 | 96.09% |
| 4 | 02:06:38 | 3712 | 4160 | 96.09% |
| 5 | 02:06:46 | 3968 | 3776 | 94.53% |
| 6 | 02:07:03 | 3712 | 4224 | 96.88% |
| 7 | 02:07:18 | 4288 | 3264 | 92.19% |
IonQ Validation — Trapped-Ion
Cross-vendor benchmarks confirm translation to trapped-ion with superior native fidelity.
ibm_kingston — Job d8uo9h1ropqc738b2kng
Depth Scaling: 5 round trips = ~30 CX equivalent. Standard SWAP would be ~35-40%. Z6 holds 70.1%.
True Topology: Rz(π) errors cause <2% variation (80.9-82.5%). Information lives in global parity.