LeGrand Shumway, Brigham Young University
Engineering
Ion traps are widely used in the field of mass spectrometry. These devices use high electric fields to mass-selectively trap, eject, and count the particles of a material, producing a mass spectrum of the given substance. Because of the usefulness of these devices, technology pushes for smaller, more portable ion traps for field use.
Although being able to characterize the electric fields within these devices would aid in the design, fabricated, and troubleshooting process, actually measuring these fields becomes increasingly difficult and in some cases impossible. This is because current electric field sensors are often too bulky or their metallic composition perturbs the electric fields they intend to measure. However, through the use of Slab Coupled Optical Sensor (SCOS) technology, we are able to build sensors that are compatible with the small spacing constraints of the ion trap. These sensors are made of purely dielectric components (a nonlinear crystal slab waveguide attached to an optical fiber) making them non perturbing to electric fields. The crystal waveguide exhibits properties such that when a laser propagates through the fiber, certain wavelengths of light will couple out of the fiber via the crystal and create “resonances” in the output light spectrum. These resonances will shift in proportion to a given applied electric field, and through passing our fiber-based sensor several through the ion trap, we can accurately model the ion trap’s electric fields. Characterizing the electric fields within an ion trap using SCOS sensor technology will greatly assist in ion trap design, fabrication, and troubleshooting techniques.