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US3701129A
Expired / Lapsed
US
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Self-biasing single wall domain arrangement
Assignee: AT&T Inc
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Filing: 1971-10-28
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Granted: 1972-10-24
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Expires: 1991-10-28
Abstract
Abstract A zero bias, single wall domain propagation arrangement is achieved by forming a layer of magnetic material in which single wall domains can be moved in stripes having dimensions to be self-biasing. A number of different types of domains are found to coexist in such strips leading to a relatively flexible storage arrangement.
Inventors
- 👤 John Alexander Copeland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:24
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0808; G11C19/0841; G11C19/0858
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
96 words
A magnetic domain arrangement comprising a layer of magnetic material of thickness h in which single-wall domains can be moved, said layer having properties and said thickness being such that for surface areas thereof having smallest dimensions greater than ten times the maximum domain diameter therein single-wall domains exist therein only in the presence of an externally supplied bias field in excess of a first value, said layer having a width w to enable domains to exist therein in the presence of an externally supplied bias field of a second value less than said first value.
Claim 2
Dependent Claim
96 words
A magnetic domain arrangement comprising a layer of magnetic material of thickness h in which single-wall domains can be moved, said layer having properties and said thickness being such that for surface areas thereof having smallest dimensions greater than ten times the maximum domain diameter therein single-wall domains exist therein only in the presence of an externally supplied bias field in excess of a first value, said layer having a width w to enable domains to exist therein in the presence of an externally supplied bias field of a second value less than said first value.
Claim 3
Dependent Claim
13 words
An arrangement in accordance with claim 1 wherein said second value is zero.
Claim 4
Dependent Claim
24 words
An arrangement in accordance with claim 2 wherein said domains have a maximum diameter Dm and wherein w is of the order of Dm.
Claim 5
Dependent Claim
14 words
An arrangement in accordance with claim 3 wherein w is approximately equal to Dm.
Claim 6
Dependent Claim
33 words
An arrangement in accordance with claim 3 wherein said layer is in the form of a stripe having an axis, and means for moving single-wall domains from stage to stage along said axis.
Claim 7
Dependent Claim
32 words
An arrangement in accordance with claim 5 also including means for defining a stable position for one of said single-wall domains to either side of said axis in each of said stage.
Claim 8
Dependent Claim
25 words
An arrangement in accordance with claim 6 wherein said stripe is in the form of a closed loop for recirculating domains past an output stage.
Claim 9
Dependent Claim
27 words
An arrangement in accordance with claim 5 also including input means for forming domains in said stripe at a first edge thereof for movement along said axis.
Claim 10
Dependent Claim
35 words
An arrangement in accordance with claim 8 wherein said input means is adapted to form single-wall domains spaced apart from first and second edges of said stripe and two-wall domains which extend between said edges.
Claim 11
Dependent Claim
22 words
An arrangement in accordance with claim 9 also including detection means coupled to said first and second edges at an output stage.
Claim 12
Dependent Claim
26 words
A magnetic domain arrangement in accordance with claim 1 whereIn said layer comprises an epitaxially deposited layer of magnetic material on a surface of a substrate.
Claim 13
Dependent Claim
26 words
A magnetic domain arrangement in accordance with claim 5 wherein said stripe comprises an epitaxially deposited layer of magnetic material on a surface of a substrate.
Claim 14
Dependent Claim
25 words
A magnetic domain arrangement in accordance with claim 3 wherein said layer comprises a plurality of epitaxially deposited stripes on a surface of a substrate.
Claim 15
Dependent Claim
99 words
A magnetic domain propagation arrangement comprising a single crystal substrate and an epitaxially grown film on a first surface thereof, said film having properties and a thickness such that for surface areas thereof having smallest dimensions greater than ten times the maximum diameter Dm of domains therein single-wall domains are present for movement only in the presence of an externally supplied bias field in excess of a first value, said film having a width about equal to Dm such that such domains are present therein in the presence of an externally supplied field of less than said first value.
Claim 16
Dependent Claim
99 words
A magnetic domain propagation arrangement comprising a single crystal substrate and an epitaxially grown film on a first surface thereof, said film having properties and a thickness such that for surface areas thereof having smallest dimensions greater than ten times the maximum diameter Dm of domains therein single-wall domains are present for movement only in the presence of an externally supplied bias field in excess of a first value, said film having a width about equal to Dm such that such domains are present therein in the presence of an externally supplied field of less than said first value.
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) | 1975-10-24 | 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 |