The diffusive spectral gap of the qubit eSWAP chain

arXiv:2610.05152 · quant-ph · Submitted 2026-10-04 · Read on arXiv

quant-ph

Submitted: 2026-10-04

Updated: 2026-10-04

Comments: 27 pages

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Terminology

• Spectral Gap — 1× in this paper · explained in 5 episodes

Sources

• Unitary designs from statistical mechanics in random quantum circuits
• iSWAP maximises the second-moment spectral gap in random quantum circuits
• Spectral gaps of ironed two-qubit gadgets matching the iSWAP gap
• Unitary Designs from Random Symmetric Quantum Circuits

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