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Updated: Jun 12, 2026
08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Summary
Researchers measured the thickness of a magnetic inert layer on a ferrite head using the longitudinal Kerr effect. The study determined possible inert-layer thicknesses ranging from 50 to 290 nanometers.
Area of Science:
- Materials Science
- Optics
- Magnetism
Background:
- Ferrite heads are crucial in magnetic recording technology.
- Understanding inert layers is key to improving head performance and longevity.
- Non-magnetic layers can affect magnetic signal integrity.
Purpose of the Study:
- To accurately measure the thickness of a magnetic inert layer on a ferrite head sample.
- To apply the longitudinal Kerr effect for precise material characterization.
- To validate experimental findings with theoretical models of magnetic stratified media.
Main Methods:
- Utilized the longitudinal Kerr effect by probing with a laser beam.
- Employed a computerized measuring system with a single detector.
- Scanned the angle of incidence of the laser beam to gather data.
- Analyzed reflection polarization information from the Kerr-reflected beam.
Main Results:
- Determined possible inert-layer thickness values.
- The measured thicknesses follow the formula (50 ± 10) + 60 x N nm.
- The order N was found to be 0, 1, 2, 3, or 4, indicating discrete possible thicknesses.
Conclusions:
- The study successfully quantified the inert layer thickness on ferrite heads.
- The results provide critical data for optimizing ferrite head design and manufacturing.
- The findings contribute to the understanding of magnetic stratified media.
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