Scientists have taken an important step toward building the powerful quantum computers of the future by shrinking a key piece of technology with the help of 3D printing.
For the first time, researchers from Lawrence Livermore National Laboratory, UC Berkeley, UC Riverside, and UC Santa Barbara have successfully miniaturized quadrupole ion traps—tiny devices that hold atoms in place so they can be used as quantum bits, or qubits.
Their results were recently published in Nature.
Ion traps are central to one of the most promising approaches in quantum computing.
They work a little like a children’s parachute game: by carefully raising and lowering different parts, you can keep a ball balanced in the middle.
In an ion trap, electric fields are used to confine ions, keeping them steady enough to act as qubits.
When cooled to their lowest energy state, these ions can store and process quantum information.
Until now, scaling up ion traps has been tricky. Traditional 3D designs offer excellent performance but are bulky, while flat “planar” versions can be mass-produced more easily but don’t perform as well.
The team realized that 3D printing might combine the strengths of both approaches. Using an advanced technique called two-photon polymerization, which allows printing with extremely fine detail, they created millimeter-scale ion traps that could confine calcium ions with precision and stability.
These printed traps proved competitive with today’s state-of-the-art devices. They achieved strong confinement, long coherence times, and low error rates.
The researchers even performed single- and two-qubit operations, including an entangling gate with 98% accuracy.
They also tested how the ions behaved under repeated use, finding that the system held up well. One test showed two calcium ions swapping positions every few minutes, a sign of reliable stability.
The process is also fast and flexible. A new trap can be printed in just 14 hours, or as little as 30 minutes if the electrodes are added to an existing surface. This opens the door for rapid prototyping and experimentation with new geometries.
By expanding the range of possible designs, the team can rethink how ion traps are optimized and even create hybrids that combine 3D and planar features.
What excites the scientists most is the potential for integration.
In the future, they hope to combine the traps with photonics and electronics directly on the same chip, making quantum systems more compact and easier to scale. Reducing sources of “noise,” or interference from the environment, is another big goal.
Because the surfaces of ion traps are a major source of error, 3D printing may allow researchers to remove unnecessary material and improve performance.
This breakthrough could influence much more than just computing. Miniaturized ion traps could be used in precision sensors, advanced atomic clocks, or compact mass spectrometers. By showing what high-resolution 3D printing can achieve, the work may also inspire new applications across science and technology.
As physicist Kristi Beck from LLNL explains, this is the kind of change that could eventually turn quantum computers from experimental devices handling a few qubits into machines capable of real, large-scale computation.
It may still take years before such systems are practical, but with this achievement, scientists are a step closer to unlocking the full power of quantum computing.
