Simulating complex quantum systems can overwhelm even powerful supercomputers. Researchers at Rice University have developed a three-dimensional ion trap that could make these systems easier to study in the laboratory.
The device works with heavy ions such as ytterbium, addressing a limitation that restricted earlier monolithic designs. Researchers from Duke University and Translume Inc. collaborated on the project.
Combining the best trap designs
Quantum simulators recreate difficult-to-model systems under controlled laboratory conditions. In trapped-ion experiments, electric fields hold charged atoms in place while lasers control their interactions. Scientists then measure the ions to understand the system they represent.
Traditional blade-style traps deliver strong performance but require manual assembly, making consistent reproduction difficult. Microfabricated chip traps offer greater precision and easier scaling, but often struggle to match their performance.
Rice physicist Guido Pagano and his colleagues wanted to combine these advantages in a compact, three-dimensional design. Earlier monolithic traps worked with lighter ions, such as calcium, but heavier species presented additional engineering challenges.
Three generations of redesign
The team started with a block of fused silica glass. Lasers and chemical processing created channels for the ions and trenches for the electrodes. Researchers then installed the electrodes and coated the structure with sputtered gold.
The trenches helped isolate the electrodes, preventing short circuits during manufacturing. They also reduced the risk of electrical breakdown under high voltages inside a vacuum.
The first prototype exposed a major problem. When researchers applied the required radio-frequency voltage, the trap developed thermal and electrical issues. It even began glowing visibly as it heated up.
A second version fixed the main flaws but introduced unwanted axial micromotion and high ion-heating rates. Both problems threatened the precise control required for reliable quantum experiments.
The third generation addressed these issues with improved heat dissipation and reduced ion movement. The researchers also used plasma-based surface treatment to lower ion-heating rates.
Pagano’s laboratory and collaborators at Duke tested the finished traps individually. Their measurements agreed with previous computer simulations, confirming that the devices performed as intended.
Expanding quantum research access
The new design could make trapped-ion experiments easier to reproduce in academic laboratories. Its compatibility with ytterbium also expands the range of ions researchers can use in monolithic three-dimensional traps.
Abhishek Menon, the study’s corresponding author and a graduate student, said solving the engineering challenges associated with heavier ions could also simplify trapping lighter species.
The technology could help researchers investigate complex processes, including charge transfer during photosynthesis. Instead of attempting to model an entire quantum system directly, scientists can use controlled experiments to understand its underlying behavior.
Roman Zhuravel, a study co-author and assistant research professor in Pagano’s laboratory, said the trap could help scientists break difficult quantum problems into manageable experiments.
The design offers laboratories another tool for studying systems that conventional computers struggle to simulate. Its engineering approach could also inform future ion traps for a wider range of quantum technologies.
The study is published in the journal Physical Review Applied.