Tuning Thermal Transport and Magnetization Dynamics in Functional Materials

In this talk, I will highlight the ongoing research efforts of our group focused on tailoring thermal transport and magnetization dynamics in functional materials for applications including active thermal control and energy-efficient spintronics. Our research leverages ultrafast laser-based metrology techniques, specifically the basic time-domain thermoreflectance and advanced time-resolved magneto-optical Kerr effect configurations. I will begin by discussing our work in solid-state control of thermal transport in nanoscale perovskite oxides, using lanthanum strontium cobaltite (LSCO) and strontium stannate (SSO) as model systems. We have successfully manipulated thermal transport through structural engineering. Notably, we have demonstrated continuous tuning of LSCO thermal conductivity by a factor of over five. This tuning is achieved via a room-temperature electrolyte-gate-induced non-volatile topotactic phase transformation from perovskite to brownmillerite, accompanied by a metal-insulator transition.<br/><br/>The second part of the talk will feature L10-FePd, a promising material candidate for energy-efficient and non-volatile spintronic devices with large areal densities. We have conducted systematical investigations into the influence of buffer-layer engineering on perpendicular magnetic anisotropy (PMA, crucial for switching speed) and Gilbert damping (related to energy consumption). Additionally, I will delve into the effects of temperature on both PMA and damping to better address the technological viability of L10-FePd for spintronic applications.