US3678478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stacking arrangement which provides self-biasing for single wall domain organizations
Assignee: AT&T Inc
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Filing: 1971-02-18
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Granted: 1972-07-18
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Expires: 1991-02-18
Abstract
Abstract Large capacity memory systems employing single wall domain devices comprise an arrangement in which layers, of materials in which domains can be moved, are stacked to form a compact component. A stacking arrangement is described which eliminates the necessity of an externally supplied bias field normally present, for practical purposes, in single wall domain devices.
Inventors
- 👤 John Alexander Copeland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 01:02
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/085
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
84 words
A magnetic arrangement comprising a stack of layers of magnetic material in each layer of which single wall domains can be moved, each of said layers having a preferred direction of magnetization out of the plane of layer and a thickness h, and means for securing said layers in fixes spaced apart relationship with respect to one another distances of about 4h whereby said layers are substantially self-biasing in the absence of an external bias field when set into a like direction of magnetization.
Claim 2
Dependent Claim
84 words
A magnetic arrangement comprising a stack of layers of magnetic material in each layer of which single wall domains can be moved, each of said layers having a preferred direction of magnetization out of the plane of layer and a thickness h, and means for securing said layers in fixes spaced apart relationship with respect to one another distances of about 4h whereby said layers are substantially self-biasing in the absence of an external bias field when set into a like direction of magnetization.
Claim 3
Dependent Claim
53 words
An arrangement in accordance with claim 1 wherein said layers comprise films deposited on substrates having thicknesses greater than h, each of said layers having associated therewith a planar arrangement for moving domains therein, wherein said means for securing said layers comprising said substrates and said planar arrangements in a solid stack arrangement.
Claim 4
Dependent Claim
39 words
An arrangement in accordance with claim 2 wherein said planar arrangement comprises a planar pattern of magnetically soft elements which provide changing pole patterns for moving domains in the adjacent layer when a reorienting in-plane field is generated therein.
Claim 5
Dependent Claim
31 words
An arrangement in accordance with claim 2 wherein said planar arrangement comprises an electrical conductor pattern for generating changing magnetic fields for moving domains in the adjacent layer when selectively pulsed.
Claim 6
Dependent Claim
21 words
An arrangement in accordance with claim 4 wherein said layers are consecutively cantilevered for exposing said conductor pattern for external connection.
Claim 7
Dependent Claim
112 words
A magnetic arrangement comprising a stack of layers of magnetic material in each layer of which single wall domains can be moved, each of said layers having a preferred direction of magnetization out of the plane of the layer and a thickness h, and means for securing said layers in fixed spaced apart relationship with respect to one another distances such that the layers when set into a like direction of magnetization provide magnetostatic fields which are of a polarity to constrict said domains, said fields being of a magnitude to reduce an externally supplied bias field from a value otherwise necessary to construct each of said domains to a prescribed geometry.
Claim 8
Dependent Claim
112 words
A magnetic arrangement comprising a stack of layers of magnetic material in each layer of which single wall domains can be moved, each of said layers having a preferred direction of magnetization out of the plane of the layer and a thickness h, and means for securing said layers in fixed spaced apart relationship with respect to one another distances such that the layers when set into a like direction of magnetization provide magnetostatic fields which are of a polarity to constrict said domains, said fields being of a magnitude to reduce an externally supplied bias field from a value otherwise necessary to construct each of said domains to a prescribed geometry.
Claim 9
Dependent Claim
50 words
A magnetic arrangement in accordance with claim 6 wherein said distances are between about 2h and 8h for providing a magnetostatic field equal to at least 50 percent of the bias field necessary to construct each of said domains to said prescribed geometry in the absence of said magnetostatic field.
Claim 10
Dependent Claim
15 words
A magnetic arrangement in accordance with claim 7 also including a high permeability enclosure thereabout.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |