Simulation Study of Laser Aberrations for MAGIS-100

The MAGIS-100 experiment is a 100-m tall atom interferometer being built at Fermilab with a goal of searching for ultralight dark matter and serving as a prototype gravitational wave detector in a frequency range between the peak sensitivities of LIGO and LISA. Wavefront aberrations in the laser used to manipulate the atoms cause phase distortions across the Sr atom cloud and result in loss of contrast and systematic errors in the interferometer phase. In this poster, we present simulation studies of the effect of wavefront aberration from the beam delivery system throughout the interferometry process. The effects of these aberrations are simulated by numerically evaluating the Rayleigh-Sommerfeld diffraction integral using the FFT convolution theorem. The aberrations are then included in a Monte Carlo simulation for determining the final interferometry phase. As a final step, we include the simulation of the imaging process. The complete simulation informed the design of the MAGIS-100 beam delivery system to minimize the aberrations experienced by the atoms, and the point-source interferometer we are simulating will be used between experimental cycles to measure wavefront aberrations.