Research Highlighs and Featured Platforms

With the miniaturization, high integration, and increased power density of electronic devices, thermal management has become one of the key factors affecting device operating efficiency, reliability, and lifespan. For micro/nano electronic devices, thermal transport properties differ significantly from those at the macroscopic scale due to size effects and quantum phenomena. Therefore, a comprehensive understanding of the thermal transport mechanisms at the nanoscale is crucial for effective thermal management in micro/nano electronic devices. The femtosecond laser time-domain thermoreflectance (TDTR) measurement system, with its ultra-high temporal (picosecond) and spatial (nanometer) resolution, is one of the most advanced technologies for micro/nano heat transfer measurement available today. 

TDTR technology is based on the temperature dependence of material surface reflectivity under the excitation of a high-frequency femtosecond laser. By measuring the periodic changes in the reflected probe light, the surface temperature fluctuations of the sample can be obtained, enabling accurate determination of the material's thermal properties and hot carrier heat dissipation characteristics. The high precision of TDTR serves as a powerful tool for experimental research on micro/nano scale heat transfer and ultrafast heat transport. It holds significant academic and application value for enhancing the understanding of heat transfer mechanisms, advancing the application and development of nanomaterials, optimizing thermal management in devices, exploring materials with novel thermal properties, and expanding energy conversion technologies.

The research team led by Professor Weidong Zheng has independently and successfully built the first TDTR system for micro/nano heat transfer measurements in Shandong Province. This system enables precise measurements of thermal properties, including thermal conductivity, interfacial thermal conductance, and heat capacity, for both bulk materials and micro/nano structures. This system can perform standard TDTR measurements and automatic scanning – TDTR measurements within the temperature range of 80 - 700 K (up to 4 - 700 K under special conditions), achieving world-leading measurement accuracy. Additionally, the system allows for the application and control of electric and pressure fields. This TDTR system stands as an internationally  competitive  measurement  platform  with first-class performance.
Based on this system, the team conducted a series of in-depth studies on phonon thermal transport characteristics and electron-phonon coupling mechanisms for materials such as two-dimensional materials and thermoelectric materials. These studies include the investigations on the interfacial thermal transport mechanism of graphene with nano vacancy defects, the heat transport mechanism of hexagonal boron nitride interfaces, and the influence of substrates on the thermal transport of metal/graphene/non-metal interfaces. These studies are of great significance for clarifying the thermal transport mechanism of two-dimensional material interfaces and achieving efficient thermal management of electronic devices.