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Title: Time-resolved scanning Kerr microscopy of flux beam formation in hard disk write heads

Abstract

To meet growing data storage needs, the density of data stored on hard disk drives must increase. In pursuit of this aim, the magnetodynamics of the hard disk write head must be characterized and understood, particularly the process of “flux beaming.” In this study, seven different configurations of perpendicular magnetic recording (PMR) write heads were imaged using time-resolved scanning Kerr microscopy, revealing their detailed dynamic magnetic state during the write process. It was found that the precise position and number of driving coils can significantly alter the formation of flux beams during the write process. These results are applicable to the design and understanding of current PMR and next-generation heat-assisted magnetic recording devices, as well as being relevant to other magnetic devices.

Authors:
; ; ;  [1]; ;  [2]; ;  [3]
  1. Department of Physics and Astronomy, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom)
  2. Research & Development, Seagate Technology, 1 Disc Drive, Springtown Industrial Estate, Derry BT48 0BF (United Kingdom)
  3. Recording Heads Operation, Seagate Technology, 7801 Computer Avenue South, Bloomington, Minnesota 55435 (United States)
Publication Date:
OSTI Identifier:
22596808
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 23; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BEAMS; DENSITY; ELECTRONIC EQUIPMENT; HEAT; IMAGES; KERR EFFECT; MAGNETIC DISKS; MICROSCOPY; RECORDING SYSTEMS; TIME RESOLUTION

Citation Formats

Valkass, Robert A. J., E-mail: rajv202@ex.ac.uk, Spicer, Timothy M., Burgos Parra, Erick, Hicken, Robert J., Bashir, Muhammad A., Gubbins, Mark A., Czoschke, Peter J., and Lopusnik, Radek. Time-resolved scanning Kerr microscopy of flux beam formation in hard disk write heads. United States: N. p., 2016. Web. doi:10.1063/1.4954018.
Valkass, Robert A. J., E-mail: rajv202@ex.ac.uk, Spicer, Timothy M., Burgos Parra, Erick, Hicken, Robert J., Bashir, Muhammad A., Gubbins, Mark A., Czoschke, Peter J., & Lopusnik, Radek. Time-resolved scanning Kerr microscopy of flux beam formation in hard disk write heads. United States. doi:10.1063/1.4954018.
Valkass, Robert A. J., E-mail: rajv202@ex.ac.uk, Spicer, Timothy M., Burgos Parra, Erick, Hicken, Robert J., Bashir, Muhammad A., Gubbins, Mark A., Czoschke, Peter J., and Lopusnik, Radek. 2016. "Time-resolved scanning Kerr microscopy of flux beam formation in hard disk write heads". United States. doi:10.1063/1.4954018.
@article{osti_22596808,
title = {Time-resolved scanning Kerr microscopy of flux beam formation in hard disk write heads},
author = {Valkass, Robert A. J., E-mail: rajv202@ex.ac.uk and Spicer, Timothy M. and Burgos Parra, Erick and Hicken, Robert J. and Bashir, Muhammad A. and Gubbins, Mark A. and Czoschke, Peter J. and Lopusnik, Radek},
abstractNote = {To meet growing data storage needs, the density of data stored on hard disk drives must increase. In pursuit of this aim, the magnetodynamics of the hard disk write head must be characterized and understood, particularly the process of “flux beaming.” In this study, seven different configurations of perpendicular magnetic recording (PMR) write heads were imaged using time-resolved scanning Kerr microscopy, revealing their detailed dynamic magnetic state during the write process. It was found that the precise position and number of driving coils can significantly alter the formation of flux beams during the write process. These results are applicable to the design and understanding of current PMR and next-generation heat-assisted magnetic recording devices, as well as being relevant to other magnetic devices.},
doi = {10.1063/1.4954018},
journal = {Journal of Applied Physics},
number = 23,
volume = 119,
place = {United States},
year = 2016,
month = 6
}
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