An in-situ method for measuring the non-linear response of a Fabry-Perot cavity

TL;DR

This paper introduces an in-situ optical method to measure the non-linear response of PZT in high finesse Fabry-Perot cavities, improving laser stabilization performance.

Contribution

The paper presents a novel differential optical technique for in-situ characterization of PZT non-linearity in Fabry-Perot cavities, enhancing measurement sensitivity and stability.

Findings

High sensitivity in measuring PZT non-linearity

Insensitive to laser and cavity drifts

Applicable for various optical lab applications

Abstract

High finesse Fabry-Perot(FP) cavity is a very important frequency reference for laser stabiliza- tion, and is widely used for applications such as precision measurement, laser cooling of ions or molecules. But the non-linear response of the piezoelectric ceramic transducer (PZT) in the FP cav- ity limits the performance of the laser stabilization. Measuring and controlling such non-linearity are important. Here we report an in-situ, optical method to characterize this non-linearity by measuring the resonance signals of a dual-frequency laser. The differential measurement makes it insensitive to laser and cavity drifting, and has a very high sensitivity. It can be applied for various applications with PZT, especially in an optical lab.