Browse Prior Art Database

Superconductor-in-Gap for Magnetic Recording Heads

IP.com Disclosure Number: IPCOM000108887D
Original Publication Date: 1992-Jun-01
Included in the Prior Art Database: 2005-Mar-23
Document File: 1 page(s) / 46K

Publishing Venue

IBM

Related People

Feng, J: AUTHOR [+3]

Abstract

Disclosed are magnetic recording heads with improved reading and writing efficiencies by use of high-temperature superconductive material in the gaps of the heads.

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This is the abbreviated version, containing approximately 83% of the total text.

Superconductor-in-Gap for Magnetic Recording Heads

      Disclosed are magnetic recording heads with improved reading
and writing efficiencies by use of high-temperature superconductive
material in the gaps of the heads.

      A typical inductive head is composed of ferrite and a thin film
gap material.  The ferrite forms a magnetic circuit.  The gap in this
circuit produces an external field during write mode, and a
sensitivity to fields when reading.

      In most head designs, the gap material is an electrical
insulator with a low magnetic permeability.  Typical examples are
glass, silicon dioxide and alumina.  The low permeability causes the
occurrence of a magnetic flux at the gap which affects head
efficiency.  The extent of these parasitic losses corresponds to
throat height and yoke length.

      In some cases, a highly conductive gap material is used to
improve writing efficiency, but does not significantly affect
readback performance.

      In contrast, superconductors possess a diamagnetic shielding
property because they permit considerable flux penetration.  This
would expel flux from the gap due to the Meissner effect.  As a
result, head efficiency would improve dramatically during both write
and read operations.

      Use of superconductive, thin film gap material has become
feasible since the discovery of high-temperature materials, also
referred to as "room temperature" or type II superconductors.  These
materials have a...