Experimental determination of nanoscale thermal transport properties in heat-assisted magnetic recording media using step-by-step time-domain thermoreflectance method

Abstract

Heat-assisted magnetic recording (HAMR) enables ultra-high areal density by locally heating magnetic recording media with high magnetic anisotropy, but the writing performance critically depends on the behavior of heat flow in its complex multilayer structure. In this work, we establish an experiment-informed approach that combines time-domain thermoreflectance (TDTR) with a step-by-step fitting strategy to extract the thermal conductivities and interfacial thermal resistances in HAMR media. These experimentally determined properties are directly implemented in finite-element method simulations, which show good agreement with reported spin-stand measurements. The TDTR-based experiment-informed modeling established in this study reliably describes a device-level behavior of HAMR and provides quantitative guidance for recording media design.