Photonics led a mixed quantum tape — Coherent +3.4% with the optics rebound — while speculative platform and isotope names fell and Arqit dropped 6.5%.

Coherent (COHR) led the quantum basket on Friday, up 3.4% to $312.62, on the lasers-and-precision-photonics chokepoint. The move had nothing to do with quantum per se: it was the optics complex rebounding alongside a broad market relief rally (S&P 500 +0.6%) after a Bloomberg report that OpenAI expects $70bn-plus annualized revenue by year-end reversed Thursday's AI-capex selloff — the same selloff that had dragged the AI-optics names down double digits a day earlier. Coherent sits on the photonics rung that quantum shares with the datacenter buildout — the lasers, fiber and optical components that both markets bid for — so when optics bounces, it carries here too. The test-and-control rung firmed with it: Keysight +2.2% to $382.75 and FormFactor +1.9% to $139.67, the cryo-CMOS and measurement names that gate qubit characterization.

The laggard was Arqit Quantum (ARQQ), down 6.5% to $17.23, a platform pure-play on quantum-safe networking with no company-specific catalyst on the day — a high-beta, sub-$1m-revenue name giving back ground in a session that rewarded hard assets over narrative. The isotopes-and-quantum-materials rung sold with it: ASP Isotopes (ASPI) −6.4% to $2.65 and Silex Systems' ADR (SILXY) −4.3% to $14.12, the enrichment-adjacent names that supply isotopically pure substrates. Sumitomo Heavy's ADR (SOHVY), a cryogenics and vacuum supplier, fell 6.3% to $9.164 — a thin ADR line, not a demand signal.

The broader tape split by rung. The gate-model platform pure-plays were mixed and modest: IonQ +1.1% to $39.89, D-Wave (QBTS) −0.2% to $14.57, Rigetti (RGTI) −0.8% to $14.03, and Quantum Computing Inc. (QUBT) −0.1% to $7.44 — no breakout in the names that trade as the sector's sentiment gauge. The qubit-fabrication-and-foundry rung lagged with the chip tape: Intel −2.2% to $104.70, AMD −2.0% to $608.10, and GlobalFoundries −2.3% to $48.24. The big-cap quantum sponsors were flat-to-up — IBM +0.2% to $227.13, Alphabet +1.0% to $351.66 — with ATI, on the specialty-metals rung, +2.0% to $191.84.

The hard catalysts are all in the next two months and all federal or conference-driven. The DARPA Quantum Benchmarking Initiative concludes Stage B and opens its Stage C down-select window around Nov 6, with selection decisions expected through mid-December — the program that will separate funded architectures from the field, directly relevant to the platform pure-plays. Q2B26 Chicago (Dec 8–10) is the industry's year-end checkpoint, and Gooch & Housego reports FY2026 results Dec 8, a read on the precision-photonics rung that led today.