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US5377141A Expired / Lapsed US ⏱️ 0.0 years remaining

Superconducting magnetic memory device having intentionally induced non-superconducting regions

Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1991-06-21
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Granted: 1994-12-27
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Expires: 2011-06-21
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Abstract

Abstract A new type of superconducting memory is described. The composition of superconducting ceramic material used in the memory has been altered in order to expedite the formation of non-superconducting regions formed of grain boundaries. Non-superconducting regions may also be formed of lattice defects. Magnetic flux is trapped within the non-superconducting regions (grain boundaries or lattice defects). Information can be stored in terms of whether or not magnetic flux is trapped.

Inventors

  • 👤 Yasuhiko Takemura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 14:57
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/44; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/831; Y10S505/832

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 89 words
A superconducting magnetic memory system comprising: a superconducting ceramic having intentionally induced, artificially occurring non-superconducting regions; cooling means for cooling said ceramic to a level lower than the critical temperature of said superconducting ceramic; means for supplying electric current passing through said ceramic; means for applying a magnetic field to said ceramic; and a voltage detector for detecting differential potentials across said non-superconducting regions in the direction of said electric current passing through said ceramic, wherein said differential potentials are caused by magnetic fluxes trapped by said non-superconducting regions.
Claim 2
Dependent Claim 89 words
A superconducting magnetic memory system comprising: a superconducting ceramic having intentionally induced, artificially occurring non-superconducting regions; cooling means for cooling said ceramic to a level lower than the critical temperature of said superconducting ceramic; means for supplying electric current passing through said ceramic; means for applying a magnetic field to said ceramic; and a voltage detector for detecting differential potentials across said non-superconducting regions in the direction of said electric current passing through said ceramic, wherein said differential potentials are caused by magnetic fluxes trapped by said non-superconducting regions.
Claim 3
Dependent Claim 79 words
An information storing and detecting method comprising: cooling a superconducting ceramic below the critical temperature of said ceramic, said superconducting ceramic having intentionally induced, artificially occurring non-superconducting regions; applying a magnetic field to said ceramic, removing said magnetic field, wherein magnetic fluxes are trapped by said non-superconducting regions; supplying electric current to said ceramic in order that a differential potential is produced at said non-superconducting regions by virtue of existence of said magnetic fluxes; and detecting said differential potential.
Claim 4
Dependent Claim 79 words
An information storing and detecting method comprising: cooling a superconducting ceramic below the critical temperature of said ceramic, said superconducting ceramic having intentionally induced, artificially occurring non-superconducting regions; applying a magnetic field to said ceramic, removing said magnetic field, wherein magnetic fluxes are trapped by said non-superconducting regions; supplying electric current to said ceramic in order that a differential potential is produced at said non-superconducting regions by virtue of existence of said magnetic fluxes; and detecting said differential potential.
Claim 5
Dependent Claim 106 words
A superconducting magnetic memory system comprising: a superconducting ceramic having artificially occurring non-superconducting regions: cooling means for cooling said ceramic to a level lower than the critical temperature of said superconducting ceramic; means for supplying electric current passing through said ceramic: and a voltage detector for detecting differential potentials across said non-superconducting regions in the direction of said electric current passing through said ceramic, wherein said differential potentials are caused by magnetic fluxes trapped by said non-superconducting regions, wherein said non-superconducting regions are formed by the use of a starting material of a composition which is intentionally deviated from a composition conforming to said superconducting ceramic.
Claim 6
Dependent Claim 106 words
A superconducting magnetic memory system comprising: a superconducting ceramic having artificially occurring non-superconducting regions: cooling means for cooling said ceramic to a level lower than the critical temperature of said superconducting ceramic; means for supplying electric current passing through said ceramic: and a voltage detector for detecting differential potentials across said non-superconducting regions in the direction of said electric current passing through said ceramic, wherein said differential potentials are caused by magnetic fluxes trapped by said non-superconducting regions, wherein said non-superconducting regions are formed by the use of a starting material of a composition which is intentionally deviated from a composition conforming to said superconducting ceramic.
Claim 7
Dependent Claim 14 words
The memory of claim 3 wherein said non-superconducting regions are formed of grain boundaries.
Claim 8
Dependent Claim 12 words
The memory of claim 3 wherein said ceramic comprises a copper oxide.
Claim 9
Dependent Claim 100 words
A superconducting magnetic memory system comprising: a superconducting ceramic having artificially occurring non-superconducting regions; cooling means for cooling said ceramic to a level lower than the critical temperature of said superconducting ceramic; means for supplying electric current passing through said ceramic; means for applying a magnetic field to said ceramic; and a voltage detector for detecting differential potentials across said non-superconducting regions in the direction of said electric current passing through said ceramic, wherein said differential potentials are caused by magnetic fluxes trapped by said non-superconducting regions, wherein said non-superconducting regions are formed by adding an impurity into said ceramic.
Claim 10
Dependent Claim 100 words
A superconducting magnetic memory system comprising: a superconducting ceramic having artificially occurring non-superconducting regions; cooling means for cooling said ceramic to a level lower than the critical temperature of said superconducting ceramic; means for supplying electric current passing through said ceramic; means for applying a magnetic field to said ceramic; and a voltage detector for detecting differential potentials across said non-superconducting regions in the direction of said electric current passing through said ceramic, wherein said differential potentials are caused by magnetic fluxes trapped by said non-superconducting regions, wherein said non-superconducting regions are formed by adding an impurity into said ceramic.
Claim 11
Dependent Claim 14 words
The memory of claim 6 wherein said non-superconducting regions are formed of grain boundaries.
Claim 12
Dependent Claim 14 words
The memory of claim 7 wherein said impurity is separated at said grain boundaries.
Claim 13
Dependent Claim 12 words
The memory of claim 6 wherein said ceramic comprises a copper oxide.
Claim 14
Dependent Claim 104 words
An information storing and detecting method comprising: cooling a superconducting ceramic below the critical temperature of said ceramic, said superconducting ceramic having non-superconducting regions; applying a magnetic field to said ceramic, removing said magnetic field, wherein magnetic fluxes are trapped by said non-superconducting regions; supplying an electric current to said ceramic in order that a differential potential is produced at said non-superconducting regions by virtue of existence of said magnetic fluxes; and detecting said differential potential, wherein said non-superconducting regions are formed by the use of a starting material of a composition which is intentionally deviated from a composition conforming to said superconducting ceramic.
Claim 15
Dependent Claim 104 words
An information storing and detecting method comprising: cooling a superconducting ceramic below the critical temperature of said ceramic, said superconducting ceramic having non-superconducting regions; applying a magnetic field to said ceramic, removing said magnetic field, wherein magnetic fluxes are trapped by said non-superconducting regions; supplying an electric current to said ceramic in order that a differential potential is produced at said non-superconducting regions by virtue of existence of said magnetic fluxes; and detecting said differential potential, wherein said non-superconducting regions are formed by the use of a starting material of a composition which is intentionally deviated from a composition conforming to said superconducting ceramic.
Claim 16
Dependent Claim 14 words
The method of claim 10 wherein said non-superconducting regions are formed of grain boundaries.
Claim 17
Dependent Claim 12 words
The method of claim 10 wherein said ceramic comprises a copper oxide.
Claim 18
Dependent Claim 90 words
An information storing and detecting method comprising: cooling a superconducting ceramic below the critical temperature of said ceramic, said superconducting ceramic having artificially occurring non-superconducting regions; applying a magnetic field to said ceramic, removing said magnetic field, wherein magnetic fluxes are trapped by said non-superconducting regions; supplying electric current to said ceramic in order that a differential potential is produced at said non-superconducting regions by virtue of existence of said magnetic fluxes; and detecting said differential potential, wherein said non-superconducting regions are formed by adding an impurity into said ceramic.
Claim 19
Dependent Claim 90 words
An information storing and detecting method comprising: cooling a superconducting ceramic below the critical temperature of said ceramic, said superconducting ceramic having artificially occurring non-superconducting regions; applying a magnetic field to said ceramic, removing said magnetic field, wherein magnetic fluxes are trapped by said non-superconducting regions; supplying electric current to said ceramic in order that a differential potential is produced at said non-superconducting regions by virtue of existence of said magnetic fluxes; and detecting said differential potential, wherein said non-superconducting regions are formed by adding an impurity into said ceramic.
Claim 20
Dependent Claim 14 words
The method of claim 13 wherein said non-superconducting regions are formed of grain boundaries.
Claim 21
Dependent Claim 14 words
The method of claim 14 wherein said impurity is separated at said grain boundaries.
Claim 22
Dependent Claim 12 words
The method of claim 13 wherein said ceramic comprises a copper oxide.

References Cited (Backward Citations)

US3995278A Cited
US4082991A Cited
US4365317A Cited
US4601015A Cited
US5011817A Cited
US5039656A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-12-26 1998-06-27 1998-12-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-12-26 2002-06-27 2002-12-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-12-26 2006-06-27 2006-12-27 $7700.00 Window Closed / Lapsed

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