Macroscopic Linear Quadrupole Ion Trap for Undergraduate Education in Electrodynamic Confinement

As the age of tech continues to evolve, there are few fields with more extensive and revolutionary prospects than quantum computing. This field of research can reshape how we approach combinatoric problems, elevating the standards of internet security, the power of machine learning, and the rate of drug discovery. Ion traps are the fundamental mechanisms for information storage in trapped ion quantum computers, so making it accessible for undergraduates to learn the basics of ion trapping can bridge the gap between cutting-edge research and practical experiential learning. With real ion trap setups easily exceeding tens or even hundreds of thousands of dollars, we created an affordable macroscopic quadrupole ion trap replica for experimentation in undergraduate lab courses. Our trap features a 4-rod setup with 4 alternating current (AC) rods defining a linear trapping region and 2 direct current (DC) electrodes confining the region on either end. Features such as an approximated parallel plate capacitor and locking lid allow students to steadily trap lycopodium particles (25μm) and observe micromotion and coulomb crystals, while the variable voltage sources allow for 1D-2D coulomb crystal transitions, filtering by charge-mass ratio, and experimenting with secular frequencies. All schematics and lab instructions for this project will be made publicly available by the end of the summer for straightforward replication at other institutions.