Quantum computers could help with drug discovery, codebreaking and materials science, but only if they grow from dozens of quantum bits (qubits) to millions. The bottleneck is control: each qubit needs precisely steered light or microwaves, and thousands of cables run into refrigerators colder than deep space. Chipmakers are trying to move that control hardware onto standard production lines, as CU Boulder's December 2025 optical modulator did.
In October 2026, Quantinuum reported five uncorrectable errors per million logical memory operations on its Helios system and targets fault-tolerant machines by 2029. IonQ's Superion 256 chip, made at its SkyWater foundry, moves qubit control onto the chip instead of laser systems, with customer deliveries set for 2027. On October 27, IBM unveiled superconducting couplers that link two 120-qubit processors with 99% state-transfer fidelity, a sign that connecting smaller chips into larger machines is working.
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Key Indicators
99.99%
Silicon qubit fidelity record
Silicon Quantum Computing's gate fidelity—qubits improve as they scale
$1B
PsiQuantum Series E funding
Raised September 2025 to build million-qubit photonic systems
2027
PsiQuantum million-qubit target
Most aggressive timeline in the industry, construction underway
4,158
Current qubit record
IBM's connected Kookaburra chips demonstrated in 2025
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22 events
Latest: October 27th, 2026 · 2 weeks ago
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October 2026
IBM Unveils Meter-Scale Superconducting L-Couplers
LatestTechnical Milestone
IBM unveiled superconducting couplers that connect two 120-qubit processors, reporting 99% state-transfer fidelity. The result is a step toward linking chips into modular machines.
RIKEN Team Runs Five Silicon Qubits at Once With 99.9% Accuracy
Technical Milestone
RIKEN researchers, publishing in Nature Physics, kept about 99.9% accuracy while five silicon spin qubits shared one microwave control line. They traced a major source of errors during simultaneous operation and reduced it.
Quantinuum Posts Near-Megaquop Error-Rate Results
Technical Milestone
Quantinuum and arXiv.org posted a paper saying its quantum computer could run about a million operations with only about five errors.
Nature Nanotechnology Review on Atom-Based Silicon Quantum Processors
Publication
A Nature Nanotechnology review says atom-based silicon quantum computers have moved from proof of concept to scalable processors. It says the remaining work is mainly industrial-scale engineering and 3D integration.
Quantinuum reported 99.9995% logical memory fidelity on Helios, about five uncorrectable errors per million operations. That is a tenfold cut from its September record.
IonQ Launches Superion 256 Chip-Based Platform
Product Launch
IonQ unveiled Superion 256, a 256-qubit trapped-ion system whose chips were fabricated at SkyWater. Control electronics sit on the chip rather than in laser systems. Customers can order now, with deliveries in 2027.
Quantinuum Wins $100 Million US Manufacturing Award
Funding Announcement
The US Department of Commerce awarded Quantinuum $100 million under the CHIPS and Science Act. The money funds semiconductor, laser and optical work for fault-tolerant trapped-ion computers.
Google Publishes Magic-State Cultivation Results in Science
Publication
Google Quantum AI reported on its Willow chip a magic-state method with 99.99% logical fidelity for T-states. The paper, published in Science, says it cut errors about 40-fold compared with uncultivated states.
December 2025
Russia Demonstrates 72-Qubit Neutral Atom System
Technical Milestone
Lomonosov Moscow State University tested 72-qubit neutral rubidium atom quantum computer with 94% two-qubit operation accuracy.
CU Boulder Unveils CMOS Quantum Control Chip
Manufacturing Breakthrough
Nature Communications published CU Boulder's CMOS-fabricated optical modulator 100x smaller than hair, using 80x less power.
SEALSQ unveiled 2026-2030 plan to commercialize silicon-based quantum computing using existing CMOS semiconductor foundries and supply chains.
Silicon Quantum Computing Achieves Record 99.99% Gate Fidelity
Manufacturing Breakthrough
Nature published SQC's silicon-based multi-register processor with 99.99% gate fidelity using CMOS-compatible manufacturing—qubits improve accuracy as they scale.
November 2025
IBM Demonstrates 4,158-Qubit System
Technical Milestone
IBM connected three Kookaburra chips into 4,158-qubit system and unveiled 120-qubit Nighthawk processor.
October 2025
Google Demonstrates Verifiable Quantum Advantage with Willow
Technical Milestone
Google's Quantum Echoes algorithm on 105-qubit Willow chip ran 13,000 times faster than classical supercomputers, marking first verifiable quantum advantage.
September 2025
PsiQuantum Raises $1 Billion for Million-Qubit Systems
Funding Announcement
PsiQuantum closed $1 billion Series E funding at $7 billion valuation to build fault-tolerant photonic quantum computers, with construction sites planned for Brisbane and Chicago.
June 2025
IBM Breaks Ground on Fault-Tolerant System
Strategic Announcement
IBM announced world's first large-scale fault-tolerant quantum computer construction in Poughkeepsie data center.
Sandia awarded $17 million for Error-Corrected Photonic Integrated Qubits Grand Challenge program.
December 2023
IBM Delivers 1,121-Qubit Condor
Technical Milestone
IBM unveiled Condor processor with 1,121 superconducting qubits, exceeding 1,000-qubit milestone.
April 2021
Intel Debuts Cryogenic Control Chip
Hardware Innovation
Intel introduced Horse Ridge II, cryogenic control chip addressing quantum computing's wiring bottleneck.
September 2020
IBM Unveils Quantum Roadmap
Strategic Announcement
IBM announced aggressive scaling roadmap targeting 1,000+ qubits by 2023 and ultimately millions of qubits.
October 2019
Google Claims Quantum Supremacy
Technical Milestone
Google's 53-qubit Sycamore processor performed calculation in 200 seconds that would take classical supercomputer 10,000 years.
Scenarios
1
CMOS Manufacturing Unlocks Million-Qubit Systems by 2030
Likely
Discussed by: IBM roadmap projections, PsiQuantum timeline, industry analysts at Bain & Company
CMOS-fabricated control hardware solves the scaling bottleneck. Semiconductor foundries begin mass-producing integrated photonic modulators, cryogenic controllers, and qubit chips using proven 300mm wafer processes. By 2029-2030, IBM delivers its Quantum Starling system with 200 logical qubits performing 100 million error-corrected operations, while PsiQuantum launches its million-qubit photonic system. Early commercial applications emerge in drug discovery and materials science. The quantum computing market expands from $3.5 billion in 2025 to over $20 billion by 2030 as practical advantage becomes demonstrable.
2
Scaling Stalls at Thousands of Qubits Through 2030s
Possible
Discussed by: Nvidia CEO Jensen Huang, conservative quantum researchers, cited in Financial Times coverage
CMOS manufacturing helps but doesn't solve all bottlenecks. Error rates remain too high, even with advanced error correction consuming most qubits for redundancy. Power consumption for cryogenic cooling scales super-linearly, making million-qubit systems economically impractical. Quantum systems plateau around 10,000-50,000 physical qubits through the early 2030s, delivering only hundreds of logical qubits. The technology finds niche applications but commercial viability remains a decade away, validating predictions that practical quantum computing requires a million-fold improvement and won't arrive until the 2040s.
3
Alternative Architecture Leapfrogs Superconducting Approach
Room-temperature or higher-temperature quantum computing approaches mature faster than expected. Photonic systems eliminate cryogenic requirements entirely. Silicon spin qubits achieve integration density that superconducting qubits cannot match. Novel architectures like QuamCore's patented design integrate a million qubits in a single cryostat—previously thought impossible. By 2030, the winning approach isn't superconducting qubits with CMOS control, but a fundamentally different architecture. IBM and Google's massive investments in superconducting systems become stranded assets as the industry pivots, echoing past technology transitions.
Historical Context
3 moments from history that rhyme with this story — and how they unfolded.
1 of 3
1960-2000
Transistor Integration and Moore's Law (1960-2000)
The semiconductor industry faced repeated scaling crises as transistor counts climbed from hundreds to billions. Each time, engineers predicted physics would halt progress. Each time, manufacturing innovations—photolithography advances, new materials, 3D architectures—extended Moore's Law. The turning point came when the industry standardized CMOS fabrication in the 1980s, enabling massive economies of scale. Companies built multi-billion dollar foundries producing millions of identical chips, driving exponential cost reductions per transistor.
Then
By 1990, CMOS manufacturing enabled microprocessors with millions of transistors at consumer prices.
Now
CMOS became the foundation of the digital revolution, with foundries producing billions of chips annually by the 2000s.
Why this matters now
Quantum computing faces an identical challenge: control systems don't scale. The CU Boulder breakthrough follows the exact playbook—adapt CMOS foundries to mass-produce quantum hardware, leveraging trillions in semiconductor investment.
2 of 3
1980-1990
IBM Mainframe Crisis and the PC Revolution (1980s)
IBM dominated computing with room-sized mainframes requiring specialized cooling and power infrastructure. When personal computers emerged using standardized components and simpler manufacturing, skeptics argued they'd never match mainframe capabilities. But standardization and mass production drove exponential cost-performance improvements. By the late 1980s, desktop machines matched mainframe power at a fraction of the cost and complexity.
Then
PC sales exploded in the mid-1980s as price-performance crossed critical thresholds for businesses and consumers.
Now
Mainframes became niche products while distributed computing on standardized hardware became the paradigm.
Why this matters now
Today's quantum computers resemble 1970s mainframes: refrigerator-sized systems with massive infrastructure. If CMOS manufacturing enables compact, standardized quantum processors, the disruption could mirror the PC revolution.
Telecommunications faced a bandwidth crisis in the 1990s as internet traffic exploded. Copper networks couldn't scale. The industry bet on fiber optics, but early systems were expensive and difficult to manufacture. Breakthroughs in optical component manufacturing—particularly CMOS-compatible photonic chips in the 2000s—enabled mass production. Optical transceivers that cost thousands of dollars dropped to tens of dollars.
Then
By 2000, fiber backbone networks began replacing copper for long-haul internet traffic.
Now
By 2010, fiber reached homes and data centers globally; photonic chips became commodities.
Why this matters now
CU Boulder's optical modulator uses the same CMOS-photonics integration that enabled cheap fiber optics. If quantum control optics follow the same cost curve, million-qubit systems become economically feasible.
