Tuning Thermal Transport and Magnetization Dynamics in Functional Materials

Transport phenomena play an important role in designing and engineering materials with tailored functionalities. This is especially true for materials with reduced dimensions. Thermal conductivity and interfacial thermal conductance, as basic transport properties of materials and interfaces, can provide a wealth of information on the fundamental scattering processes of charge and thermal carriers with structural defects, boundaries, and interface imperfection. In this talk, I will share our group's activities in advancing the state-of-the-art ultrafast optical metrology to study the thermal and magnetic properties of functionalized materials spanning a wide range of applications. This will include: (1) tuning thermal transport in single crystals of correlated perovskite oxides; (2) revealing the 3D anisotropic thermal transport in black phosphorus as a "wonder material" for the semiconductor industry; (3) seed-layer engineering of low-damping materials with perpendicular magnetic anisotropy for spintronic applications. Last but not least, I will briefly highlight our effort in studying the magnetization dynamics of complex structures, including perpendicular synthetic antiferromagnets and Co/Pd multilayers with spin-strain coupling. The structure-property relationships of functional materials revealed by the ultrafast pump-probe technique open up opportunities for tailoring material properties by structural engineering at the atomic and molecular levels. Ultimately, such an understanding can be leveraged to guide the design and optimization of materials, as promising building blocks for high-performance electronic devices, thermal management, solid-state energy conversion, spintronics, and data storage.