US3701127A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic domain propagation arrangement including medium with graded magnetic properties
Assignee: AT&T Inc
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Filing: 1971-03-31
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Granted: 1972-10-24
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Expires: 1991-03-31
Abstract
Abstract The movement of single wall domains in an internal layer of a film of magnetic material permits operation unencumbered by surface defects or interactions with substrates on which the film is formed for bias fields over a range which is large compared to the range of bias fields characteristic of films in which single wall domains extend from surface to surface.
Inventors
- 👤 Andrew Henry Bobeck
- 👤 Hyman Joseph Levinstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:38
CPC Classifications
H; H01; H01F; H01F10/00; G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0808; G11C19/0816; G11C19/085; G11C19/0858; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
46 words
An arrangement in accordance with claim 1 wherein said magnetic properties comprise a magnetic moment which varies from a prescribed value at said surface to a maximum at a first distance from said surface and to said prescribed value at a second distance from said surface.
Claim 2
Dependent Claim
35 words
An arrangement in accordance with claim 1 wherein said magnetic properties comprise a magnetic moment which varies from a prescribed value at said surface to a minimum at a first distance from said first surface.
Claim 3
Dependent Claim
28 words
An arrangement in accordance with claim 3 wherein said magnetic moment increases to said prescribed value at a second distance from said surface greater than said first distance.
Claim 4
Dependent Claim
21 words
An arrangement in accordance with claim 1 including means for providing a bias field of a polarity to constrict said domains.
Claim 5
Dependent Claim
18 words
An arrangement in accordance with claim 5 also including means for moving single wall domains in said layer.
Claim 6
Dependent Claim
55 words
An arrangement in accordance with claim 6 wherein said means for moving comprises magnetic elements having geometries and being disposed to exhibit attracting domain patterns which change in a manner to move said domains along a path from input to output positions in response to a magnetic field reorienting in the plane of said layer.
Claim 7
Dependent Claim
37 words
An arrangement in accordance with claim 7 also including means for providing single wall domains in said path at said input position selectively and means for detecting the presence and absence of domains at said output position.
Claim 8
Dependent Claim
66 words
An arrangement comprising a layer of material in which single wall domains can be moved and having first and second surfaces, said layer having a gradient in its magnetic properties along an axis normal to said surfaces to define a plurality of different sublayers therein for sustaining domains of different diameters, and bias means for constricting domains to a diameter sustained in one of said sublayers.
Claim 9
Dependent Claim
64 words
A magnetic arrangement comprising a layer of material in which single wall domains can be moved, said layer comprising a first surface and being characterized by a variation in magnetic moment with distance from said first surface, said variation being such that single wall domains in said layer are confined to increasingly smaller thicknesses of said layer for increasingly higher values of bias field.
Claim 10
Dependent Claim
56 words
A magnetic arrangement comprising a layer of material in which single wall domains can be moved, said layer comprising a first surface and being characterized by a change in magnetic properties with distance from said first surface, said change being such that domains in said layer occur indifferent sublayers thereof at different values of bias field.
Claim 11
Dependent Claim
20 words
A magnetic arrangement in accordance with claim 11 wherein said change in magnetic properties comprises a change in magnetic moment.
Claim 12
Dependent Claim
64 words
A magnetic arrangement in accordance with claim 12 wherein said layer is chaRacterized by a magnetic moment of a first value and includes a surface sublayer wherein said magnetic moment is of a second value higher than said first value such that in the presence of a bias field in excess of a first value single wall domains occur only in said surface sublayer.
Claim 13
Dependent Claim
22 words
A magnetic arrangement in accordance with claim 13 wherein said layer is formed as an epitaxially grown film on a nonmagnetic substrate.
Claim 14
Dependent Claim
35 words
A magnetic arrangement in accordance with claim 13 also including biasing means for providing a bias field in excess of said first value for maintaining domains in said surface sublayer at a nominal operating size.
Claim 15
Dependent Claim
17 words
A magnetic arrangement in accordance with claim 15 also including means for moving domains in said layer.
References Cited (Backward Citations)
US3540019A
Cited
US3643238A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |