Neutral atoms instead of superconductors: how Hanyuan-2 works

Most known quantum computers — including Google's Willow system and IBM processors — use superconducting qubits. These systems require extreme cooling to temperatures near absolute zero (typically around 10–15 millikelvin), achieved using so-called dilution refrigerators. These are not only expensive but also energy-intensive — the cooling alone can require over 20 kW.

Hanyuan-2 takes a completely different approach. It works with neutral rubidium atoms trapped in an optical lattice using laser tweezers (so-called optical tweezers). Each atom functions as a single qubit, and lasers serve both to hold the atom in place and to perform quantum operations. This approach does not require extreme cooling of superconducting circuits — laser cooling of atoms to microkelvin temperatures suffices, which is technologically simpler and more energy-efficient.

Low power consumption is one of the most interesting parameters of Hanyuan-2. While a superconducting quantum computer with 200 qubits would require tens of kilowatts, Hanyuan-2 reportedly manages with less than 7 kW. For perspective: that's about as much as a standard home oven or two electric kettles.

Two cores, two isotopes: why it matters

The biggest innovation of Hanyuan-2 is its dual-core architecture. The system contains two separate quantum processors, each with 100 qubits — one using atoms of the rubidium-85 isotope, the other the rubidium-87 isotope.

Why two different isotopes of the same element? Rubidium-85 and rubidium-87 differ in the number of neutrons in the nucleus, which affects their quantum properties. Each isotope has slightly different energy levels and different sensitivity to external interference. By using two different isotopes in two parallel processors, researchers can perform calculations that would not be possible on a single type of qubit, while simultaneously comparing results between both cores for error detection and correction.

This architecture resembles the evolution of classical computer processors. In the 1990s and early 21st century, chip manufacturers like Intel and AMD struggled with physical limits of increasing clock speeds in single-core processors. The solution became multi-core architectures — instead of one faster core, they began using multiple cores working in parallel. Hanyuan-2 suggests that a similar path could work in the quantum world as well.

Quantum noise and stability: qubits' biggest enemy

Quantum computers suffer from a fundamental problem: qubits are extremely fragile. Any external interference — electromagnetic fields, temperature fluctuations, or even cosmic radiation — can cause loss of quantum information. This phenomenon is called decoherence and is the main obstacle to scaling quantum systems.

Neutral atoms have a natural advantage in this regard. Unlike superconducting qubits, which are artificially made and each is slightly different, rubidium atoms are completely identical — nature "manufactures" them with perfect precision. This means more consistent behavior and fewer errors. The dual-core design of Hanyuan-2 additionally allows one core to serve as a reference for the other, which should further improve the ability to detect and correct errors.

According to the researchers behind Hanyuan-2, the dual-core design could improve stability and reduce quantum noise — two parameters that directly affect how many useful operations can be performed on a quantum computer before the qubits "break". In the field of neutral atoms, this is a significant step, because qubit stability is the key factor for future scaling to thousands and millions of qubits.

How Hanyuan-2 compares to the competition

In the field of neutral atoms, China is not the only player. The American startup QuEra (spin-off from Harvard and MIT) operates a 256-qubit system and plans scaling to thousands of qubits. French Pasqal, founded by Nobel laureate Alain Aspect, supplies neutral atom quantum processors to European research centers including the German Jülich Supercomputing Centre.

In the superconducting world, Google leads with the Willow processor (105 qubits) and IBM with the Condor processor (1,121 qubits). However, the number of qubits is not everything — their quality is also crucial, measured by so-called fidelity of operations and resilience to errors.

Hanyuan-2 with 200 qubits and power consumption below 7 kW is, per qubit, very energy-efficient. For comparison: the superconducting IBM Q System One consumes significantly more energy for cooling and operation, even with a smaller number of qubits. Energy efficiency will play an increasingly important role, especially given growing pressure on data center sustainability.

What it means for Europe and the Czech Republic

The European Union is investing billions of euros in quantum technologies through the Quantum Flagship program and the EuroHPC initiative, which plans to build a network of quantum computers across member states. In June 2025, the Czech AI Factory project was launched in Ostrava, combining supercomputing and AI capacities. Direct involvement of quantum hardware in the Czech Republic is still in its early stages, but research groups at CTU, Palacký University, and Masaryk University are actively engaged in quantum technologies.

The report on Hanyuan-2 comes at a time when quantum computers are slowly moving from academic laboratories to the commercial sphere. European companies like Pasqal already offer cloud access to quantum processors. Hanyuan-2 is not yet commercially available even in China, let alone in Europe, but its architecture shows the direction the field is heading: modularity, energy efficiency, and practical scalability.

Quantum computers and AI: a connection that makes sense

Quantum computing and artificial intelligence are increasingly overlapping. NVIDIA recently released open-source models for qubit stabilization, which we have already written about at Jarvis AI. A hybrid approach — where a classical AI model controls and corrects quantum operations — could significantly accelerate the path to practically usable quantum computers.

Hanyuan-2 with its dual-core architecture fits into this story: it represents a step toward modular systems where individual quantum cores can be combined and managed similarly to how we orchestrate containers in the cloud today. And AI could be the tool that enables such orchestration.