International Laser Safety Conference (ILSC)

Laser system for the 100-meter-tall MAGIS-100 atom interferometer

Kenneth DeRose

Published Mar 1, 2023• 0 citations

Abstract

MAGIS-100 is a 100-meter atom interferometer currently being built at Fermilab and will be the worlds largest atom fountain. It will leverage modern atom optics techniques to search for dark matter, perform quantum atomic experiments, and detect gravitational waves at frequencies inaccessible to LIGO and LISA. Generation and precise control of meter-separated quantum atomic superpositions within the interferometer requires an agile laser system able to rapidly shift the optical frequency up to a rate of 100 GHz/s while maintaining a phase lock to our static frequency comb. To meet the power requirement of the experiment, the two interferometry lasers are coherently locked and must be robust to rapid frequency shifts. The interferometry laser's spatial mode is cleaned through fiber coupling and long free space propagation in vacuum with frequency noise introduced by the fiber suppressed by a PID lock. In addition to the scientific and technical hurdles in this experiment, there are complex laser safety issues. There are a total of twenty-four lasers and seven wavelengths ranging from 50mW to 100W, all within the same LCA.

DOI: 10.2351/7.0001472

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