Visible to the public Using Ensemble Waveform Analysis to Compare Heat Assisted Magnetic Recording Characteristics of Modeled and Measured Signals

TitleUsing Ensemble Waveform Analysis to Compare Heat Assisted Magnetic Recording Characteristics of Modeled and Measured Signals
Publication TypeJournal Article
Year of Publication2017
AuthorsHernández, S., Lu, P. L., Granz, S., Krivosik, P., Huang, P. W., Eppler, W., Rausch, T., Gage, E.
JournalIEEE Transactions on Magnetics
Volume53
Pagination1–6
ISSN0018-9464
KeywordsCBD, channel bit density, compositionality, cross-track offset, cross-track position, di-bit extraction method, down-track profile, ensemble waveform analysis, Heat assisted magnetic recording (HAMR), Heat-assisted magnetic recording, magnetic recording, Media, media noise, micromagnetic, micromagnetically modeled heat assisted magnetic recording waveforms, Noise measurement, pubcrawl, remanence, remanence SNR, resilience, Resiliency, Signal to noise ratio, signal to noise ratio (SNR), temperature, Temperature measurement, track edges, transition SNR, waveform analysis, windowing functions
Abstract

Ensemble waveform analysis is used to calculate signal to noise ratio (SNR) and other recording characteristics from micromagnetically modeled heat assisted magnetic recording waveforms and waveforms measured at both drive and spin-stand level. Using windowing functions provides the breakdown between transition and remanence SNRs. In addition, channel bit density (CBD) can be extracted from the ensemble waveforms using the di-bit extraction method. Trends in both transition SNR, remanence SNR, and CBD as a function of ambient temperature at constant track width showed good agreement between model and measurement. Both model and drive-level measurement show degradation in SNR at higher ambient temperatures, which may be due to changes in the down-track profile at the track edges compared with track center. CBD as a function of cross-track position is also calculated for both modeling and spin-stand measurements. The CBD widening at high cross-track offset, which is observed at both measurement and model, was directly related to the radius of curvature of the written transitions observed in the model and the thermal profiles used.

URLhttps://ieeexplore.ieee.org/document/7572903/
DOI10.1109/TMAG.2016.2612230
Citation Keyhernandez_using_2017