Optimal Aperture Sizing to Minimize Power and Mode Mismatch Losses in Gaussian Beam Propagation

Losses in optical experiments are critical and arise from various sources and require careful identification, analysis, and mitigation. This paper focuses on Gaussian beam propagation through circular apertures, examining both optical and mode mismatch losses. Traditional rules for aperture size become insufficient at precision levels below 1 ppm, necessitating a more detailed analysis, including lateral misalignment effects. By refining aperture selection criteria, this work enhances prior studies to meet modern experimental constraints. These results are particularly relevant for large-scale optical systems, such as gravitational wave detectors, where minimizing losses is essential for achieving the required sensitivity and performance.