**Preface**

This book, sponsored by the Special Issue entitled "Optoelectronic Materials, Devices, and Applications", is devoted to gathering a broad array of research papers on the latest advances in the development of optoelectronic materials and devices of semiconductors, fiber optics, power electronics, microwaves, and terahertz. Each of the included papers highlights the latest principles, methods, and potential applications of optoelectronics. The primary aim of this Special Issue is to promote cross-disciplinary research in optoelectronics. It is our sincere hope that these advances will provide new inspiration for the development and application of optoelectronic materials and devices. We would like to give our thanks to all of the authors and peer reviewers who contributed to this Special Issue.

> **Pingjuan Niu , Li Pei, Yunhui Mei, Hua Bai, and Jia Shi** *Editors*
