The Daily · Sunday 25 October 2026

The day in brief

Treasury proposed adding quantum-computing software and algorithms to U.S. investment restrictions that already cover quantum hardware and related systems ¹. The proposal is not yet in force, and public comment is open through December 7, 2026 ¹. A lattice-surgery compiler reported 55.6% lower space–time volume in geometric mean and compiled 75.5× faster than the evaluated DasCot configuration ².

Monarch Quantum says it is supplying integrated photonics for Infleqtion’s work on NASA’s Quantum Gravity Gradiometer Pathfinder ³. A Delft-led team resolved nuclear-spin transitions in a single titanium-47 atom using scanning tunnelling microscopy and electron–nuclear double resonance ⁴. A quantum model of cavity haloscopes predicts axion-induced photon-count statistics that differ from a Poisson model, while finding nonclassical axion effects remain out of reach ⁵.

A Rocq paper reports a machine-checked proof of composable, finite-key BB84 security, while a separate Lean paper describes an end-to-end theorem ⁶. On Quantinuum’s 56-qubit H2-2, researchers tested unary and Dicke encodings, while classical simulations favored untested binary quadrature ⁷. IIT Patna researchers applied a hybrid quantum similarity algorithm to numerical atomtronics simulations to identify nonlinearity that could support magnetic-field sensing ⁸.

The five

• Treasury Proposes Wider Controls on Quantum Investment

  Treasury has proposed expanding outbound investment restrictions to cover software and algorithms for quantum technologies, alongside controls on quantum hardware and related systems. The proposal is open for public comment through December 7, 2026, while existing rules remain in effect.

  Source · U.S. Department of the Treasury

• Wang et al.’s Dynamic Architecture Cuts Lattice-Surgery Compilation Time 75.5×

  A lattice-surgery compiler reallocates routing space as a quantum circuit runs, reporting lower space–time volume and faster compilation than DasCot. The paper’s evaluation also describes the benchmark set, modeling assumptions and tradeoffs behind those results.

  Source · arXiv

• Monarch Supplies Photonics for NASA’s Quantum Gravity Pathfinder

  Monarch Quantum says it is supplying integrated photonics hardware for Infleqtion’s work on NASA’s Quantum Gravity Gradiometer Pathfinder. The space-based sensor is designed to measure tiny variations in Earth’s gravity, with a flight demonstration expected in 2030.

  Source · Monarch Quantum

• Delft Researchers Resolve Nuclear Spin Transitions in One Titanium Atom

  A Delft-led team used scanning tunnelling microscopy and electron–nuclear double resonance to resolve transitions in the nucleus of a single titanium-47 atom. Measurements across magnetic-field strengths revealed how hyperfine and quadrupole interactions shape the spectrum and showed the nucleus could be addressed when its coupling to the electron spin was weak.

  Source · Nature Communications

• Researchers Build a Quantum Measurement Model for Axion Searches

  Six researchers present a fully quantum model of continuous axion-dark-matter measurements in cavity haloscopes. Their calculations predict photon-count statistics that differ from the Poisson model often used for coherent signals, while finding that intrinsically nonclassical axion effects remain out of reach.

  Source · Continuous Measurement of Quantum Axion Dark Matter

Also today

• Rocq and Lean Teams Formalize BB84 Security in Separate Proofs
• 56-Qubit H2-2 Test Reveals Bosonic Encoding Trade-Offs
• IIT Patna Team Connects Quantum Similarity Testing to Atomtronics
• Quantum Feedback Equation Models Finite-Response Detectors
• BIRD Funds Qarakal–Quantum Elements Catalysis MVP
• Innsbruck Team Reports Trapped-Ion Gate Errors Below 0.5%

The paper of the day

• Traceable Quantum Secret Sharing

Every issue

1. Sunday 1 November 2026 — Luthra and Owens Demonstrate QLDPC Surgery on Quantinuum H2-2
2. Saturday 31 October 2026 — IDEMIA Wins First EMVCo Certification for PQC Payment Cards
3. Friday 30 October 2026 — One Transmon Connects Two Superconducting Waveguides
4. Thursday 29 October 2026 — Researchers Demonstrate a Single-Molecule Spin–Photon Interface
5. Wednesday 28 October 2026 — USTC Researchers Demonstrate Four-Way Multiplexed Quantum Gates
6. Tuesday 27 October 2026 — IBM Team Entangles Logical Qubits on Nighthawk Processor
7. Monday 26 October 2026 — Intel Agrees to Acquire Classiq for Full-Stack Quantum Computing
8. Sunday 25 October 2026 — Treasury Proposes Wider Controls on Quantum Investment
9. Saturday 24 October 2026 — Treasury Proposes Wider Controls on Quantum Investment
10. Friday 23 October 2026 — Single-Ion Error Correction Extends Qubit Lifetime 12.9-Fold
11. Thursday 22 October 2026 — Oxford Stores Remote Ion Entanglement in Calcium for 10 Seconds