Patent US3836898A successfully refreshed from Google Patents.
US3836898A
Expired / Lapsed
US
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Magnetic bubble structure for suppression of dynamic bubble conversion
Assignee: AT&T Inc
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Filing: 1973-10-09
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Granted: 1974-09-17
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Expires: 1993-10-09
Abstract
Abstract The dynamic conversion of a normal magnetic bubble to a relatively low mobility form during high-speed operation of bubble devices is suppressed in structures which tolerate only negligible changes in the magnetic configuration of the wall of the bubble.
Inventors
- 👤 F Hagedorn
- 👤 A Bobeck
- 👤 J Geusic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:40
CPC Classifications
H; H01; H01F; H01F10/00; G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0858
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
137 words
A magnetic structure for the movement of single wall domains, said structure comprising a first layer of material in which single wall domains can be moved, said domains being characterized by changes in the magnetization configuration of the domain wall thereabout when displaced in said layer at a relatively high velocity, said structure including means coupled to said layer for suppressing said changes by allowing only negligible Bloch line formation in the walls of said domains wherein said means includes a nonmagnetic layer coupled to said first layer and a second layer of material in which single wall domains can be moved, said nonmagnetic layer having a thickness to inhibit exchange coupling between the magnetic spins of said first and second layers and permitting magnetostatic coupling between domains in corresponding positions of said first and second layers.
Claim 2
Dependent Claim
137 words
A magnetic structure for the movement of single wall domains, said structure comprising a first layer of material in which single wall domains can be moved, said domains being characterized by changes in the magnetization configuration of the domain wall thereabout when displaced in said layer at a relatively high velocity, said structure including means coupled to said layer for suppressing said changes by allowing only negligible Bloch line formation in the walls of said domains wherein said means includes a nonmagnetic layer coupled to said first layer and a second layer of material in which single wall domains can be moved, said nonmagnetic layer having a thickness to inhibit exchange coupling between the magnetic spins of said first and second layers and permitting magnetostatic coupling between domains in corresponding positions of said first and second layers.
Claim 3
Dependent Claim
26 words
A structure in accordance with claim 1 wherein said first and second layers and said nonmagnetic layer are epitaxially formed on a single crystal nonmagnetic substrate.
Claim 4
Dependent Claim
23 words
A structure in accordance with claim 2 also including an ion implanted surface region in said second layer for suppressing hard bubbles therein.
Claim 5
Dependent Claim
26 words
A structure in accordance with claim 3 wherein said first layer includes first and second sublayers of high and low moment for suppressing hard bubbles therein.
Claim 6
Dependent Claim
107 words
A magnetic structure for the movement of single wall magnetic domains, said structure comprising first and second layers of magnetic material in which single wall magnetic domains can be moved, said structure also including a nonmagnetic layer separating said first and second layers and having a sufficient thickness to prevent exchange coupling between said first and second layers, said layers having properties and geometries and being disposed such that a magnetic domain and an associated substantially identical domain are formed in said first and second layers respectively, and said domain in said first layer is magnetostatically coupled to an associated domain in the other of said layers.
Claim 7
Dependent Claim
107 words
A magnetic structure for the movement of single wall magnetic domains, said structure comprising first and second layers of magnetic material in which single wall magnetic domains can be moved, said structure also including a nonmagnetic layer separating said first and second layers and having a sufficient thickness to prevent exchange coupling between said first and second layers, said layers having properties and geometries and being disposed such that a magnetic domain and an associated substantially identical domain are formed in said first and second layers respectively, and said domain in said first layer is magnetostatically coupled to an associated domain in the other of said layers.
Claim 8
Dependent Claim
115 words
A magnetic structure comprising a first layer of material in which single wall domains can be moved, said first layer having first and second surfaces, each of said domains extending through said first layer between said surfaces and having a domain wall thereabout, said first layer being characterized by a preferred magnetization direction normal to the plane of said layer, said structure also including a second layer contiguous said second surface, said second layer having properties and being disposed to constrain the magnetization of said wall at said second surface to a peripheral orientation in the plane of said wall at high drive field frequencies wherein normal bubbLes tend to be converted into hard bubbles.
Claim 9
Dependent Claim
115 words
A magnetic structure comprising a first layer of material in which single wall domains can be moved, said first layer having first and second surfaces, each of said domains extending through said first layer between said surfaces and having a domain wall thereabout, said first layer being characterized by a preferred magnetization direction normal to the plane of said layer, said structure also including a second layer contiguous said second surface, said second layer having properties and being disposed to constrain the magnetization of said wall at said second surface to a peripheral orientation in the plane of said wall at high drive field frequencies wherein normal bubbLes tend to be converted into hard bubbles.
Claim 10
Dependent Claim
85 words
A magnetic structure in accordance with claim 6 wherein said second layer comprises a nonmagnetic layer and said structure also includes a third layer of material in which single wall domains can be moved, said third, second and first layers being formed in succession by epitaxial techniques on a single crystal magnetic substrate, said second layer having a thickness to allow magnetostatic coupling between like-positioned domains in said first and third layers and to inhibit exchange coupling between spins in said first and third layers.
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) | 1977-09-16 | 1978-03-18 | 1978-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-16 | 1982-03-18 | 1982-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-16 | 1986-03-18 | 1986-09-17 | $7700.00 | Window Closed / Lapsed |