Measuring thermal properties of materials is not only of fundamental importance in understanding the transport processes of energy carriers (electrons and phonons) but also of practical interest in developing novel materials with desired thermal conductivity for applications in energy, electronics, and photonic systems. Over the past two decades, ultrafast laser-based time-domain thermoreflectance (TDTR) has emerged and evolved as a reliable, powerful, and versatile technique to measure the thermal properties of a wide range of bulk and thin film materials and their interfaces. This tutorial discusses the basics as well as the recent advances of the TDTR technique and its applications in the thermal characterization of a variety of materials. The tutorial begins with the fundamentals of the TDTR technique, serving as a guideline for understanding the basic principles of this technique. A diverse set of TDTR configurations that have been developed to meet different measurement conditions are then presented, followed by several variations of the TDTR technique that function similarly as the standard TDTR but with their own unique features. This tutorial closes with a summary that discusses the current limitations and proposes some directions for future development.

中文翻译：

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教程：时域热反射 (TDTR) 用于体材料和薄膜材料的热性能表征

测量材料的热性能不仅对于理解能量载体（电子和声子）的传输过程具有根本重要性，而且对于开发具有所需热导率的新型材料用于能源、电子和光子系统也具有实际意义。在过去的二十年中，基于超快激光的时域热反射 (TDTR) 已经出现并发展成为一种可靠、强大且通用的技术，用于测量各种体膜和薄膜材料及其界面的热性能。本教程讨论了 TDTR 技术的基础知识和最新进展及其在各种材料的热表征中的应用。本教程从 TDTR 技术的基础开始，作为理解该技术基本原理的指南。然后介绍了为满足不同测量条件而开发的一组多样化的 TDTR 配置，然后是 TDTR 技术的几种变体，其功能与标准 TDTR 类似，但具有自己的独特功能。本教程以讨论当前限制并提出一些未来发展方向的总结结束。