Simple piezoelectric-actuated mirror with 180 kHz servo bandwidth

TL;DR

This paper introduces a high bandwidth piezoelectric mirror actuator capable of stabilizing optical cavity lengths with a servo bandwidth of 180 kHz, surpassing previous PZT-based devices and enabling advanced optical control applications.

Contribution

The paper presents a novel piezoelectric-actuated mirror with a record-high servo bandwidth of 180 kHz, significantly improving precision control in optical systems.

Findings

Achieved a 180 kHz servo bandwidth with flat amplitude response.

Maintained over 135° phase margin up to 200 kHz.

Demonstrated potential for improved optical length stabilization.

Abstract

We present a high bandwidth piezoelectric-actuated mirror for length stabilization of an optical cavity. The actuator displays a transfer function with a flat amplitude response and greater than 135$^\circ$ phase margin up to 200 kHz, allowing a 180 kHz unity gain frequency to be achieved in a closed servo loop. To the best of our knowledge, this actuator has achieved the largest servo bandwidth for a piezoelectric transducer (PZT). The actuator should be very useful in a wide variety of applications requiring precision control of optical lengths, including laser frequency stabilization, optical interferometers, and optical communications.