Kerr imaging of a thin film magnetic transducer to measure thin film head fields

Wolfson, J.; Bain, J.A.

doi:10.1109/20.951299

Cited by 6 publications

(2 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2 shows a typical pattern of medium response for a 5 ns field pulse of 55 mA. (estimated field of 400 kA/m [9]), including both the out-of-plane and in-plane magnetization components. For the in-plane component, a large amplitude is identified in the mid-of-gap, where large in-plane fields are expected.…”

Section: Resultsmentioning

confidence: 99%

“…The write head is driven by a variable delay pulse generator followed by a fast current driver, capable of delivering 0.8 ns risetime pulsed magnetic field, synchronized with respect to the laser pulses. The magnetic field amplitude of this particular write head has been calibrated in a separate experiment by J. T. Wolfson et al [9], using a soft-magnetic indicator layer with in-plane anisotropy. The response of the recording medium is probed using the magneto-optical Kerr effect.…”

Section: Experimental Techniquementioning

confidence: 99%

See 1 more Smart Citation

Sub-nanosecond non-Arrhenius magnetic switching in perpendicular multilayers

Veerdonk

Svedberg

et al. 2001

IEEE Trans. Magn.

Self Cite

View full text Add to dashboard Cite

Measurements are presented of sub-nanosecond magnetization reversal processes of perpendicularly magnetized (CoCr/Pt) multilayers using real-time Kerr microscopy. The multilayers are placed on a ring-type recording head which is used as a sub-ns risetime field source. In the gap of the write head the magnetic field direction changes rapidly from in-plane to out-of-plane. By scanning the laser beam across the gap the influence of the field angle on the reversal process is studied. The reversal time depends critically on the field angle, and faster switching occurs close to the gap (pole edge) due to the increase of the in-plane field. On the time scale of the study, the rotational (non-Arrhenius) switching seems to dominate.Index Terms-High-speed switching, non-Arrhenius switching, perpendicular recording, time-resolved Kerr microscopy.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Experimental Techniquementioning

confidence: 99%

Sub-nanosecond non-Arrhenius magnetic switching in perpendicular multilayers

Veerdonk

Svedberg

et al. 2001

IEEE Trans. Magn.

Self Cite

View full text Add to dashboard Cite

show abstract

Micromagnetic study of subnanosecond magnetic switching in perpendicular multilayers

Lyberatos

Veerdonk

et al. 2002

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

Dynamic Kerr imaging of soft underlayers for perpendicular recording applications (invited)

Wolfson¹,

Bain

Khizroev

et al. 2002

Journal of Applied Physics

View full text Add to dashboard Cite

Time-resolved Kerr imaging was used to examine the magnetization dynamics of soft underlayers (SULs) within perpendicular magnetic recording media. Two media configurations were examined with permalloy SULs of 20 and 200 nm thickness. The media in both of these samples were 14 nm thick Co/Pt multilayer films separated from the soft underlayer by a thin exchange decoupling layer of Ta. For comparison, two equivalent SUL samples were examined with no media layer. The media were examined while driven at 80 MHz by one of two types of magnetic recording heads: a 2.5 μm track width longitudinal head, and a 1 μm track width perpendicular recording head. The rise time (10%–90%) of the fields from the heads was ∼1.4 ns. It was observed in the SUL films without media, that the film switching speeds were similar to that of the driving head, for both longitudinal and perpendicular heads. The switching speed of the SUL films with a recording layer was slower due to influence of the recording layer on the magnetic properties of the SUL. In the 200 nm thick SUL-only film, the integration of the normal magnetization at the back surface of the medium indicates that approximately half of the flux generated by the write head passes out through the back of the film. The switching behavior seen in the films with media were significantly different from the films without media. The switching seen on the back surface of the 20 nm SUL with media was confined to the area directly over the pole tips. For the 200 nm with media, the switching was more active past the track edges than directly over the pole tips.

show abstract

Kerr imaging of a thin film magnetic transducer to measure thin film head fields

Cited by 6 publications

References 6 publications

Sub-nanosecond non-Arrhenius magnetic switching in perpendicular multilayers

Sub-nanosecond non-Arrhenius magnetic switching in perpendicular multilayers

Micromagnetic study of subnanosecond magnetic switching in perpendicular multilayers

Dynamic Kerr imaging of soft underlayers for perpendicular recording applications (invited)

Contact Info

Product

Resources

About