Coercivity-gradient bi-layered thin-film media for longitudinal recording

AbstractSuperlattice structures, consisting of SrCuO2, (Sr,Ca)CuO2, and BaCuO2 layers in the tetragonal, "infinite layer" crystal structure, have been grown by pulsed-laser deposition (PLD). Superlattice chemical modulation is observed for structures with component layers as thin as a single unit cell (~3.4 Å), indicating that unit-cell control of (Sr,Ca)CuO2 growth is possible using conventional pulsed-laser deposition over a wide oxygen pressure regime. X-ray diffraction intensity oscillations, due to the finite thickness of the film, indicate that these films are extremely flat with a thickness variation of only ~20 Å over a length scale of several thousand angstroms. Using the constraint of epitaxy to grow metastable cuprates in the infinite layer structure, novel high-temperature superconducting structural families have been formed. IN particular, epitaxially-stabilized SrCuO2/BaCuO2 superlattices, grown by sequentially depositing on lattice-matched (100) SrTiO3 from BaCuO2 and SrCuO2 ablation targets in a PLD system, show metallic conductivity and superconductivity at Tc(onset) ~70 K. these results show that pulsed-laser deposition and epitaxial stabilization have been used to effectively "engineer" artificially-layered thin-film materials.

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As-deposited crystalline barium ferrite thin film media for longitudinal recording

Journal of Magnetism and Magnetic Materials ◽

10.1016/0304-8853(95)00538-2 ◽

1996 ◽

Vol 153 (1-2) ◽

pp. 246-254 ◽

Cited By ~ 14

Author(s):

Jinshan Li ◽

Robert Sinclair ◽

Stephen S. Rosenblum ◽

Hidetaka Hayashi

Keyword(s):

Thin Film ◽

Barium Ferrite ◽

Longitudinal Recording

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Simulation of Contact Behavior of the Thin Film of Hard Disk at Head/Disk Interface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.2339 ◽

2011 ◽

Vol 287-290 ◽

pp. 2339-2342

Author(s):

Hong Rui Ao ◽

Deng Pan ◽

Hong Yuan Jiang

Keyword(s):

Thin Film ◽

Hard Disk Drives ◽

Hard Disk ◽

Hertzian Contact ◽

Von Mises Stress ◽

Head Disk Interface ◽

Disk Interface ◽

Slider Motion ◽

Von Mises ◽

Layered Thin Film

The contact at head/disk interface in hard disk drives subject to an external shock has been studied using the finite element method. A rigid cylinder moving over a two-layered thin film was implemented to simulate the contact between the recording slider and the disk. The effects of different friction coefficients on the von Mises stress of two-layered thin film were investigated. The relation between pressed depth and width of deformation has been obtained. Results show that the amplitude decreases with increase of friction coefficient while the period of slider motion is diminution. In addition, the stress distribution fits Hertzian contact theory.

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