I. Introduction
Recent high areal density demonstrations of 1 Tb/in2 [1]–[4], [11] and higher, 3000 kFCI linear density [5], 1 million tracks per inch demonstrations [6], and successful drive integration [7]–[9] all have catapulted the heat-assisted magnetic recording (HAMR) technology into magnetic data storage device productization. The current stage of the HAMR integration into drives signifies the resolution of significant technical challenges [5], [10], [13].