Dynamic Stability Analysis for Surfing Head-Disk Interface

Reducing the head-media spacing is of crucial importance in enabling future high density magnetic recording. Fly and lubricant contact interface, or surfing recording, is one of the possible interface solutions for 5 ~ 10 Tb/in² of magnetic recording. One major challenge for surfing interface schemes is how to sustain the dynamic stability of the head disk interface (HDI). This paper explores the mechanism of slider´s dynamic stability at near contact regimes, by means of a simulation study considering air bearings, surface adhesion and slider-lubricant and slider-disk contacts. The simulation results reveal that there are four HDI states, i.e. flying, bouncing, surfing and sliding states, when the slider approaches the disk. One major mechanism of HDI instability is due to the multiple stable equilibrium positions of HDI system. Minimizing the critical contact force by proper HDI design is the key to realize the lube-surfing scheme from the viewpoint of HDI dynamics and stability.