Geometric tilt-to-length coupling in precision interferometry: mechanisms and analytical descriptions

Abstract Tilt-to-length (TTL) coupling is a technical term for the cross-coupling of angular or lateral jitter into an interferometric phase signal. It important noise source in precision interferometers and originates either from changes optical path lengths wavefront clipping effects. Within this paper, we focus on geometric TTL categorise it number different mechanisms which give analytic expressions. We then show that description not always sufficient to predict within interferometer. We, therefore, discuss how understanding effects allows reduction already by smart design choices. Additionally, they can be used counteract total measured system. The presented content applies large variety interferometers, including space gravitational wave detectors like LISA.