Laser-heating-based active optics for synchrotron radiation applications

TL;DR

This paper introduces a laser-heating-based active optics method for precise x-ray mirror surface correction in synchrotron radiation facilities, demonstrating sub-nanometer deformation control and free-form surface modulation.

Contribution

It presents a novel laser-heating technique for mirror surface correction that achieves high precision and flexibility, advancing active optics in synchrotron applications.

Findings

Laser power as low as milliwatts can induce sub-nanometer surface deformation.

Spot size variation effectively modulates the deformation response.

The method successfully corrects free-form mirror surfaces.

Abstract

Active optics has attracted considerable interest from researchers in synchrotron radiation facilities, because of its capacity for x-ray wavefront correction. Here, we report a novel and efficient technique for correcting or modulating a mirror surface profile based on laser-heating-induced thermal expansion. An experimental study of the characteristics of the surface thermal deformation response indicates that the power of a milliwatt laser yields a bump height as low as sub-nanometer scale, and that variation of the spot size modulates the response function width effectively. In addition, the capacity of the laser-heating technique for free-form surface modulation is demonstrated via a surface correction experiment. The developed method is a promising new approach towards effective x-ray active optics coupled with at-wavelength metrology techniques.