EAGER: Quantum Manufacturing: 3D Microfabricated Ion Traps

Engineered quantum devices promise to revolutionize communication, sensing, and computation, but these systems must increase in size by orders of magnitude if they are to be useful for real-world problems. In particular, trapped atomic ions are a leading platform for quantum information processing. These ions are trapped in dc and rf electric potentials, controlled with lasers, and measured optically. However, current approaches to ion trapping face a tradeoff between scalability and trap quality (e.g., the depth and uniformity of the trapping potential). This EArly-concept Grant for Exploratory Research (EAGER) Quantum Manufacturing award supports development of a new ion trap architecture providing both electrical and optical control, without sacrificing manufacturability. Silicon fabrication techniques will be explored to create electrodes that increase optical access, a multi-wafer alignment and bonding process will improve trap quality, and thin focusing optics will be directly fabricated and aligned with the trapping electrodes. These advancements will enable trapping, controlling, and measuring thousands of individual ions across a centimeter-scale device. This work represents the first steps towards defining the manufacturing process for a trapped ion quantum computer. Additionally, the growing quantum industry will need a trained workforce to design, build, and test these next-generation devices. By participating in the research, students will be trained in pertinent skills and develop a quantum literacy. Special effort will be made to broaden participation of underrepresented populations by joining with existing efforts at the University of Washington. This project aims to develop a manufacturing process capable of reliably integrating electrical and optical components necessary for high fidelity, scalable quantum computing with trapped ions, closing the gap between the trapping characteristics and the scalability of the design. Research will focus on development of a reproducible fabrication process for ion traps with simultaneously high trap depth, voltage efficiency, and optical access. Research in and development of advanced Silicon fabrication techniques will achieve overhanging electrodes and backside routing. Multi-layer wafer traps will provide high quality trapping potentials, and electrostatic simulations will inform manufacturing tolerances. Finally, planar focusing optics for improved collection and control will be designed and lithographically aligned to electrodes by direct patterning of handle wafer on either side of the wafer trapping electrodes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.