Patent US4169189A successfully refreshed from Google Patents.
US4169189A
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Magnetic structure
Assignee: US Philips Corp
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Filing: 1977-06-27
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Granted: 1979-09-25
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Expires: 1997-06-27
Abstract
Abstract A magnetic structure for the propagation of magnetic bubbles at elevated velocity. A magnetic bubble layer is grown on a [110] face of a substrate, the lattice misfit being between -6×10 -3 and -2×10 -3 , and the magnetic layer having a composition on the basis of europium-iron garnet and a damping parameter ≦3×10 -7 Oe 2 sec/rad.
Inventors
- 👤 William T. Stacy
- 👤 Antonius B. Voermans
- 👤 Hans Logmans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:17
CPC Classifications
H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/18; H01F10/20; H01F10/24; H01F10/26; H01F10/28; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
122 words
A magnetic structure suitable for the high velocity propagation of single wall magnetic domains in the structure, comprising a monocrystalline, non-magnetic substrate having a lattice constant a 1 and having a surface bearing a single layer of a monocrystalline europium based rare earth-iron garnet material having a lattice constant a 2 , an easy axis of magnetisation substantially normal to the plane of the layer and with a medium axis of magnetisation in the plane of the layer, the said substrate surface extending substantially parallel to a {110} face of the substrate with the damping parameter λ 1 of the magnetic material not exceeding 3×10 -7 Oe 2 sec/rad, while -6×10 -3 <(a 1 -a 2 ) /a 2 <-2×10 -3 .
Claim 2
Dependent Claim
122 words
A magnetic structure suitable for the high velocity propagation of single wall magnetic domains in the structure, comprising a monocrystalline, non-magnetic substrate having a lattice constant a 1 and having a surface bearing a single layer of a monocrystalline europium based rare earth-iron garnet material having a lattice constant a 2 , an easy axis of magnetisation substantially normal to the plane of the layer and with a medium axis of magnetisation in the plane of the layer, the said substrate surface extending substantially parallel to a {110} face of the substrate with the damping parameter λ 1 of the magnetic material not exceeding 3×10 -7 Oe 2 sec/rad, while -6×10 -3 <(a 1 -a 2 ) /a 2 <-2×10 -3 .
Claim 3
Dependent Claim
46 words
A magnetic structure as claimed in claim 1, wherein the substrate comprises Gd 3 Ga 5 O 12 material and the magnetic layer comprises a (Eu A) 3 (Fe B) 5 O 12 material, wherein A is Lu, Tm and/or Yb B is Al and/or Ga.
Claim 4
Dependent Claim
51 words
A magnetic structure as claimed in claim 1, wherein the substrate comprises a Gd 3 Ga 5 O 12 material and the magnetic layer comprises a (Eu A C) 3 (Fe D) 5 O 12 material, wherein A is Lu, Tm and/or Yb C is Ca and/or Sr D=ge and/or Si.
Claim 5
Dependent Claim
25 words
A magnetic structure as claimed in claim 1, wherein the magnetic layer has been grown on the surface of the substrate by liquid phase epitaxy.
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) | 1982-09-24 | 1983-03-26 | 1983-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-24 | 1987-03-26 | 1987-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-24 | 1991-03-26 | 1991-09-25 | $7700.00 | Window Closed / Lapsed |