HAMR Noise Mechanism Study With Spin-Stand Testing

In this paper, we present a spin-stand testing study of heat-assisted magnetic recording (HAMR). Motivated by the understanding of the major recording noise mechanisms predicted by previous modeling, experiments were made to investigate the recording field/write current dependence of signal-to-noise ratio. The two significant noise mechanisms in HAMR, incomplete switching and erase-after-write, have been observed in the experiments and shown to be similar to the previous modeling results. Previous simulations indicate that system performance strongly correlates with recording time window (RTW). Therefore, head/media relative velocity was varied to change the RTW, and the effects of linear velocity are also compared. Further analysis has been applied to cases with different writer and media components. These results help understand the field/media requirements to optimize the HAMR recording system performance.