Patent US3714640A successfully refreshed from Google Patents.
US3714640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Single wall domain propagation arrangement
Assignee: AT&T Inc
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Filing: 1971-05-28
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Granted: 1973-01-30
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Expires: 1991-05-28
Abstract
Abstract An external means for supplying a bias field of a polarity to contract single wall domains employed to insure the stability of single wall domains in a layer of a host magnetic material has been found to be unnecessary if a surface layer of the host material is prepared so that the surface is permanently magnetized normal to the plane of the host layer and exchangecoupled to the body of that layer.
Inventors
- 👤 A Bobeck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:11
CPC Classifications
H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/18; H01F10/20; H01F10/24; G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0808; G11C19/0841; G11C19/085
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
91 words
A domain propagation arrangement comprising a first layer of magnetic material in which single wall domains can be moved, said layer being characterized by a preferred direction of magnetization along an axis out of the plane of said layer and having a surface layer and a body layer, said surface layer being effectively permanently set in a direction along said axis and exchange coupled to said body layer, and means for moving single wall domains in said body layer in a manner to avoid changing the magnetization in said surface layer.
Claim 2
Dependent Claim
91 words
A domain propagation arrangement comprising a first layer of magnetic material in which single wall domains can be moved, said layer being characterized by a preferred direction of magnetization along an axis out of the plane of said layer and having a surface layer and a body layer, said surface layer being effectively permanently set in a direction along said axis and exchange coupled to said body layer, and means for moving single wall domains in said body layer in a manner to avoid changing the magnetization in said surface layer.
Claim 3
Dependent Claim
91 words
A domain propagation arrangement comprising a first layer of magnetic material in which single wall domains can be moved, said layer being characterized by a preferred direction of magnetization along an axis out of the plane of said layer and having a surface layer and a body layer, said surface layer being effectively permanently set in a direction along said axis and exchange coupled to said body layer, and means for moving single wall domains in said body layer in a manner to avoid changing the magnetization in said surface layer.
Claim 4
Dependent Claim
91 words
A domain propagation arrangement comprising a first layer of magnetic material in which single wall domains can be moved, said layer being characterized by a preferred direction of magnetization along an axis out of the plane of said layer and having a surface layer and a body layer, said surface layer being effectively permanently set in a direction along said axis and exchange coupled to said body layer, and means for moving single wall domains in said body layer in a manner to avoid changing the magnetization in said surface layer.
Claim 5
Dependent Claim
20 words
An arrangement in accordance with claim 1 wherein said axis is substantially normal to the plane of said first layer.
Claim 6
Dependent Claim
16 words
An arrangement in accordance with claim 2 wherein said body layer comprises an epitaxially grown crystal.
Claim 7
Dependent Claim
30 words
An arrangement in accordance with claim 2 wherein said body layer comprises a crystal of epitaxial garnet having a strained surface layer for maintaining a preset condition of magnetization therein.
Claim 8
Dependent Claim
24 words
An arrangement in accordance with claim 2 wherein said body layer comprises epitaxial garnet and said surface layer comprises a relatively high coercivity layer.
Claim 9
Dependent Claim
18 words
An arrangement in accordance with claim 5 wherein said body layer comprises epitaxially grown europium erbium gallium garnet.
Claim 10
Dependent Claim
17 words
An arrangement in accordance with claim 5 wherein said surface layer comprises a rare earth cobalt alloy.
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) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |