'Enchilada Trap' paves the way for better quantum computers

Sandia National Laboratories has produced its first lot of an ion trap, a central component for certain quantum computers. The device, dubbed the ‘Enchilada Trap’, enables scientists to build more powerful machines to advance the experimental field of quantum computing. In addition to the traps operated at Sandia, several traps will be used at Duke University for performing quantum algorithms. An ion trap is a type of microchip that holds electrically charged atoms, or ions. With more trapped ions, or qubits, a quantum computer can run more complex algorithms.

With sufficient control hardware, the Enchilada Trap could store and transport up to 200 qubits using a network of five trapping zones inspired by its predecessor, the Roadrunner Trap. According to Daniel Stick, a Sandia scientist and leading researcher with the Quantum Systems Accelerator, a quantum computer with up to 200 qubits and current error rates will not outperform a conventional computer for solving useful problems. However, it will enable researchers to test an architecture with many qubits that in the future will support more sophisticated quantum algorithms for physics, chemistry, data science, materials science and other areas. “We are providing the field of quantum computing room to grow and explore larger machines and more complicated programming,” Stick said.

Sandia has researched, built and tested ion traps for 20 years, combining institutional knowledge with new innovations. For the Enchilada Trap, the researchers needed space to hold more ions and a way to rearrange them for complex calculations. The solution was a network of electrodes that branches out, much like a family tree; each narrow branch serves as a place to store and shuttle ions. Sandia also experimented with similar junctions in previous traps. The Enchilada Trap uses the same design in a tiled way so it can explore scaling properties of a smaller trap. Stick said the branching architecture is currently the best solution for rearranging trapped ion qubits and forecast that future, larger versions of the trap will feature a similar design.

The dissipation of electrical power on the Enchilada Trap presented another challenge, as it can generate significant heat, leading to increased outgassing from surfaces, a higher risk of electrical breakdown and elevated levels of electrical field noise. To address this issue, production specialists designed new microscopic features to reduce the capacitance of certain electrodes.

“We collaborated with scientists and engineers to learn about the kind of technology, features and performance improvements they will need in the coming years. We then design and fabricate traps to meet those requirements and constantly seek ways to further improve,” said Zach Meinelt, the lead integrator on the project.

Image caption: The ‘Enchilada Trap’, manufactured in Sandia National Laboratories’ Microsystems Engineering, Science and Applications fabrication facility. Image credit: Craig Fritz