Patent US3887905A successfully refreshed from Google Patents.
US3887905A
Expired / Lapsed
US
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Magnetic domain shifting arrangement employing movable strip domain
Assignee: AT&T Inc
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Filing: 1973-01-29
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Granted: 1975-06-03
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Expires: 1993-01-29
Abstract
Abstract Magnetic crystals have been found capable of structuring themselves into information channels under certain magnetic conditions. A propagation mechanism for moving magnetic domains, such as bubbles, along channels so defined has been discovered also. The dimensions of the channel and the size of the bubbles movable along the channel depend on material properties rather than on photolithographic resolution. Thus, the necessity for photolithographic processing previously employed for defining the familiar bubble movement implementations is eliminated, and both packing densities and yields are expected to be extremely high.
Inventors
- 👤 Andrew Henry Bobeck
- 👤 Henry Evelyn Derrick Scovil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:03
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0858; G11C19/0808; G11C19/0816
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
144 words
Magnetic apparatus comprising a first layer of magnetic material having properties such as to be capable of having a domain wall formed therein in response to the presence of a magnetic field in a first range, said wall extending between first and second positions in a manner to form an information channel therebetween in the absence of propagation-assisting physical structures, first means coupled to said layer for introducing a magnetic indication of information to said channel at said first position, and second means also coupled to said layer for detecting said magnetic indication of information at said second position, said magnetic indication being moveable from said first to said second position in the presence of a magnetic field in said first range, said wall having properties such as to be operative in the presence of a magnetic drive field to move said indication therealong.
Claim 2
Dependent Claim
144 words
Magnetic apparatus comprising a first layer of magnetic material having properties such as to be capable of having a domain wall formed therein in response to the presence of a magnetic field in a first range, said wall extending between first and second positions in a manner to form an information channel therebetween in the absence of propagation-assisting physical structures, first means coupled to said layer for introducing a magnetic indication of information to said channel at said first position, and second means also coupled to said layer for detecting said magnetic indication of information at said second position, said magnetic indication being moveable from said first to said second position in the presence of a magnetic field in said first range, said wall having properties such as to be operative in the presence of a magnetic drive field to move said indication therealong.
Claim 3
Dependent Claim
144 words
Magnetic apparatus comprising a first layer of magnetic material having properties such as to be capable of having a domain wall formed therein in response to the presence of a magnetic field in a first range, said wall extending between first and second positions in a manner to form an information channel therebetween in the absence of propagation-assisting physical structures, first means coupled to said layer for introducing a magnetic indication of information to said channel at said first position, and second means also coupled to said layer for detecting said magnetic indication of information at said second position, said magnetic indication being moveable from said first to said second position in the presence of a magnetic field in said first range, said wall having properties such as to be operative in the presence of a magnetic drive field to move said indication therealong.
Claim 4
Dependent Claim
144 words
Magnetic apparatus comprising a first layer of magnetic material having properties such as to be capable of having a domain wall formed therein in response to the presence of a magnetic field in a first range, said wall extending between first and second positions in a manner to form an information channel therebetween in the absence of propagation-assisting physical structures, first means coupled to said layer for introducing a magnetic indication of information to said channel at said first position, and second means also coupled to said layer for detecting said magnetic indication of information at said second position, said magnetic indication being moveable from said first to said second position in the presence of a magnetic field in said first range, said wall having properties such as to be operative in the presence of a magnetic drive field to move said indication therealong.
Claim 5
Dependent Claim
20 words
Magnetic apparatus in accordance with claim 1 also including third means for moving said magnetic indication controllably along said channel.
Claim 6
Dependent Claim
22 words
Magnetic apparatus in accordance with claim 2 wherein said first layer comprises a material characterized by a domain wall having undulations therein.
Claim 7
Dependent Claim
20 words
Magnetic apparatus in accordance with claim 3 wherein said third means comprises means for moving said undulations along said wall.
Claim 8
Dependent Claim
26 words
Magnetic apparatus in accordance with claim 4 wherein said third means comprises means for generating a magnetic drive field reorienting in the plane of said layer.
Claim 9
Dependent Claim
50 words
Magnetic apparatus in accordance with Claim 5 wherein said first means comprising a second layer of magnetic material coupled to said first layer and capable of having single wall domains moved therein, and means for selectively generating in said second layer a pattern of single wall domains representative of information.
Claim 10
Dependent Claim
23 words
Magnetic apparatus in accordance with claim 6 wherein said second means comprises a detector of single wall domains coupled to said second layer.
Claim 11
Dependent Claim
46 words
Magnetic apparatus in accordance with claim 2 wherein said third means includes a second layer coupled to said first layer and having properties to form a strip domain wall corresponding to the wall of the strip domain wall in said first layer and having undulations therein.
Claim 12
Dependent Claim
51 words
Magnetic apparatus in accordance with claim 8 wherein said first means comprising a third layer of magnetic material coupled to said second layer and being capable of having single wall domains moved therein, and means for selectively generating in said third layer a pattern of single wall domains representative of information.
Claim 13
Dependent Claim
19 words
Magnetic apparatus in accordance with claim 3 wherein said first layer comprises a material characterized by conical domains therein.
Claim 14
Dependent Claim
94 words
Magnetic apparatus comprising a layer of material in which magnetic domain walls can be moved, first means for establishing a magnetically significant boundary along a path between first and second positions in said layer, second means for defining along said path a magnetic domain wall structure having a periodic geometry which changes symmetrically with respect to said boundary in response to a magnetic field reorienting cyclically, said wall being coupled to said boundary in a manner to provide an imbalance in said changes in geometry during a portion of the cycle of said field.
Claim 15
Dependent Claim
94 words
Magnetic apparatus comprising a layer of material in which magnetic domain walls can be moved, first means for establishing a magnetically significant boundary along a path between first and second positions in said layer, second means for defining along said path a magnetic domain wall structure having a periodic geometry which changes symmetrically with respect to said boundary in response to a magnetic field reorienting cyclically, said wall being coupled to said boundary in a manner to provide an imbalance in said changes in geometry during a portion of the cycle of said field.
Claim 16
Dependent Claim
19 words
Magnetic apparatus in accordance with claim 11 wherein said magnetic field reorients cyclically in the plane of said layer.
Claim 17
Dependent Claim
25 words
Magnetic apparatus in accordance with claim 12 including means for introducing information to and means for detecting information at said first and second positions, respectively.
Claim 18
Dependent Claim
19 words
Magnetic apparatus in accordance with claim 13 wherein said first means for establishing said boundary comprises a domain wall.
Claim 19
Dependent Claim
18 words
Magnetic apparatus in accordance with claim 14 wherein said first means comprises a crystallographic axis of said layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |