IonQ, Pasqal and Atom Computing: Google's Fierce Rivals in the Quantum Computing Revolution

🏁 The qubit race has more than one lane

When Google announced quantum supremacy with Sycamore in 2019 and IBM unveiled Condor with 1,121 qubits in December 2023, the conversation centered on superconducting circuits. Yet superconductors are not the only technology capable of building a quantum computer. Three smaller companies — IonQ, Pasqal and Atom Computing — compete using radically different physical principles: trapped ions and neutral atoms. Comparing them reveals that the road to useful quantum computers will most likely not be a single path.

⚡ IonQ: The trapped-ion pioneer

IonQ was founded in 2015 by Christopher Monroe and Jungsang Kim, professors at the University of Maryland and Duke University respectively. Their technology is based on an idea first proposed by Ignacio Cirac and Peter Zoller in 1995: trapping atomic ions in electromagnetic fields and using lasers to manipulate quantum states. The Paul trap — which earned Wolfgang Paul the Nobel Prize in Physics in 1989 — uses radio frequencies to keep charged particles suspended in a vacuum.

Monroe had begun his research at NIST alongside David Wineland (Nobel Prize in Physics 2012), where they built the first controllable quantum logic gates using trapped ions. The advantages of this architecture are impressive: hyperfine qubits maintain their coherence for thousands to millions of years in theory — effectively the most stable qubits that exist. Initialization reaches a fidelity of >99.9%, measurement accuracy exceeds 99.99%, and two-qubit gates surpass 99% fidelity according to experimental data.

IonQ went public on the NYSE in October 2021, raising $636 million. In February 2024, it inaugurated the first quantum computing factory in the US in Bothell, Washington. Its quantum computers are available through Amazon Web Services, Microsoft Azure and Google Cloud. In January 2026 the company announced an acquisition of SkyWater Technology for $1.8 billion — a sign it aims for vertical integration, from chip manufacturing to quantum processors.

🔬 Neutral atoms: The alternative approach

Unlike ions, neutral atom technology uses atoms without electrical charge — typically rubidium, caesium, ytterbium or strontium — trapped in magneto-optical traps and manipulated with optical tweezers. Qubits are encoded in the atoms' energy levels, and entangling gates rely on a phenomenon called the Rydberg blockade.

When an atom is excited to a Rydberg state — meaning to a very high principal quantum number — its interaction with neighboring atoms becomes twelve orders of magnitude stronger compared to the ground state. This means that if one atom is in a Rydberg state, its neighbors cannot be excited — a natural control mechanism that functions as a quantum gate. In practice, physics does the job that in superconductors requires engineering.

The French company Pasqal, based near Paris, was founded in 2019 by researchers at the Institut d'Optique and uses neutral atom arrays. The American Atom Computing follows a similar architecture. In December 2023, a Harvard and MIT team (Bluvstein et al.) demonstrated a processor of 48 logical qubits based on reconfigurable atom arrays — a milestone for the entire field. Entangling gate fidelity in state-of-the-art experiments reaches 99.7%, while single-qubit gates approach 99.9%.

🔄 Three technologies, three philosophies

Comparing the three most important architectures reveals fundamental differences in design philosophy:

Superconducting processors (IBM, Google) operate at temperatures near absolute zero — roughly 15 millikelvin — inside dilution refrigerators. Their qubits (transmon) are artificially fabricated circuits on silicon chips. The advantage: they can scale quickly to large numbers of qubits. The disadvantage: high error rates due to thermal noise and short coherence times (microseconds).

Trapped ions (IonQ) offer exceptional accuracy and full connectivity — each qubit can interact directly with every other without intermediate steps. However, critics point to slow gate operation times and the relatively large size of the equipment. As of December 2023, the largest number of controllably entangled ions was 32.

Neutral atoms (Pasqal, Atom Computing) combine gate speed with massive scalability potential — optical tweezers can position hundreds or thousands of atoms in two-dimensional or three-dimensional arrays. Real-time reconfiguration is a unique advantage. However, the technology is newer and gate reliability has not yet matched trapped ions in benchmarks.

🚀 From startup to industry

The most interesting aspect of this competition is not technical but industrial. During 2025, IonQ completed a series of acquisitions worth billions: Oxford Ionics ($1.1 billion), ID Quantique (quantum cryptography), Lightsynq Technologies (photonic interconnects), Capella Space ($311 million — satellite imaging for quantum key distribution QKD from space) and Vector Atomic (quantum sensors). The company is building an integrated ecosystem, from sensors and satellites to cryptography and processors.

Pasqal, by contrast, follows a European strategy: close collaboration with research institutes, funding from European programs and a focus on specialized simulation applications. Atom Computing operates in the spectrum between research prototype and commercial platform.

🎯 The battle will be decided by error correction

Ultimately, the technology that will dominate will be the one that first solves the problem of quantum error correction. Each architecture faces different challenges: superconductors need a vast number of physical qubits per logical qubit, ions must overcome scaling beyond a few dozen qubits, and neutral atoms must further improve gate fidelity.

DARPA's decision to include 11 companies — among them IonQ — in the Quantum Benchmarking Initiative shows that not even the US government is betting on a single technology. The goal is to assess whether a useful quantum computer can be built by 2033. The answer may not come from superconductors, but from ions held in electromagnetic traps or neutral atoms parked in laser beams.