MRI: Acquisition of Coupled Wavemeters for Precise Excitation of Charged and Neutral Particles

Middlebury College, Middlebury VT

Investigators

Abstract

Through a process called laser cooling, dilute gasses of atoms can be slowed and confined, levitating inside ultra-pure steel vacuum chambers. At this point the trapped atoms can be used for next generation applications, like voltage sensing or the simulation of microscopic crystal structure. To pursue such applications, the principal investigators plan to use two different exotic atoms, rubidium and ytterbium, which each require several lasers with vastly different colors to successfully laser cool. These lasers’ colors will span from the ultraviolet to infrared regions of the spectrum of light, and levitation can only happen if the energy of the packets of laser light (laser photons) is precisely measured and controlled to within about 0.0001%. This Major Research Instrumentation project funds a pair of high precision devices called wavemeters to measure the photon energies with sufficient accuracy. The two meters, which are designed to function in different parts of the light spectrum, will be networked together with fiber optic cables, enabling both principal investigators to have access to the full measurement range in their physically separate labs. These advanced measurement capabilities will not only generate new scientific results, but also help generate meaningful research projects for undergraduate students at Middlebury College. The principal investigators (Goodsell and Hess) are planning experiments using, respectively, launched cold rubidium atoms in highly excited Rydberg states and chains of multiple isotopes of trapped cold ytterbium ions. These particles require excitation light between 370 and 1250 nm for transitions that are hard to determine by secondary observation such as absorption spectroscopy. This Major Research Instrumentation project funds a network of Fizeau and Michelson wavelength meters (wavemeters) to make real-time measurements of laser wavelength. To span the entire spectrum required by both research groups, the network will consist of two wavemeters with different wavelength sensitivity ranges and sufficient measurement speed to stabilize lasers with feedback from the wavemeters. The wavemeters will be connected to each PI's research space using fiber optic links and multiplexed fiber switches, therefore allowing the full range of lasers required by each research group to be monitored simultaneously. With this instrumentation, the principal investigators advance two areas of research: observations of Rydberg atoms subject to the spatially-dependent force of a charged wire, which highlight the Stark effect in a quantum regime, and experiments co-trapping ions of different isotopic species in order to study their efficacy as sympathetic coolants for qubit ions. 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.