# introduction

The parameter-shift rule is a workhorse for the optimization of parametrized quantum circuits. In this post, I explain how it also works in a noisy context and how we can extend it to convex combinations of quantum channels. This blog post is a summary of Appendix A of our paper A variational toolbox for quantum multi-parameter estimation ¹.

I recently gave a talk entitled Einführung in variationelle Quantenalgorithmen (Introduction to variational quantum algorithms) within the PlanQK Webinar series. The talk is in German and aimed at an audience without a particular physics background.