To get a quantum computer to do anything, you have to make individual atoms interact in a controlled way. Most neutral-atom companies do this by hitting atoms with lasers to push them into a high-energy state. The atoms interact, then the state decays quickly. The operation has to finish before the decay.
These two teams used a different method. They cooled lithium atoms to near absolute zero, trapped them in a grid made of laser light, and let neighboring atoms overlap slightly. No high-energy state needed. The atoms touch in a controlled, predictable way, and that touch becomes the logic operation. The ETH Zurich group and the Max Planck group used different control schemes and landed at similar fidelities.
The teams also reported Bell-state lifetimes over 10 seconds. A Bell state is a pair of qubits locked together so that measuring one determines the other, no matter how far apart they sit. The lifetime is how long that link survives before noise breaks it. Many quantum platforms measure this in microseconds or milliseconds. Ten seconds is a long window, and it matters because every gate operation has to finish before the link decays.
Lithium matters here for a specific reason. Its electrons follow a rule that no two of them can occupy the same state at the same time. That rule, built into the physics, prevents a whole category of errors automatically. The hardware handles some of the error checking that software would otherwise have to do.
The likely first use for machines like this is quantum chemistry. Simulating a drug molecule or a battery material means simulating how electrons behave. Lithium atoms in this setup follow the same rules as those electrons, so the hardware and the problem use the same physics. The phys.org writeup has details.

