Observing and Modeling the Chirping Effect in Acousto-Optic Modulators

Abstract

Acousto-optic modulators (AOMs) are used in many atomic, molecular, and optical experiments. This paper analyzes the transient phase called the phase chirp that happens when the AOM is switched on and off. An optical setup is used to measure the phase chirp from the AOM. By decomposing the data into sine and cosine components, the phase chirp can more easily be measured and seen visually. A model is also presented to explain how experimental considerations, such as the angle of alignment with a fiber cable and circuit parameters, could cause the chirp. The model presents a parameter, (\Phi), which is linear in terms of the alignment angle, and the model predicts that changing the alignment will affect the chirping effect. Fitting the model to the experimental data reveals that the model explains most of the chirping effect.