US4397912A
Expired / Lapsed
US
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Garnet film for magnetic bubble element
Assignee: Hitachi Ltd
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Filing: 1981-06-29
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Granted: 1983-08-09
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Expires: 2001-06-29
Abstract
Abstract Herein disclosed is a magnetic garnet film for a magnetic bubble element, in which the temperature changing rate of a bubble collapse field is reduced by Gd and Ga and in which the operating characteristics of the bubbles are improved by La and Lu. The temperature coefficient of the bubble collapse field is -0.24 to 0%/ DEG C., and the operating characteristics are remarkably excellent, therefore, this garnet film is suitable for the small bubbles with a diameter smaller than or equal to 1 mu m.
Inventors
- 👤 Norio Ohta
- 👤 Keikichi Ando
- 👤 Yuzuru Hosoe
- 👤 Yutaka Sugita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:23
CPC Classifications
H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/18; H01F10/20; H01F10/24; H01F41/00; H01F41/14; H01F41/24; H01F41/28; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10S428/91; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
81 words
A garnet film on a substrate, for a magnetic bubble element, said garnet film having such a composition as is expressed by a general formula of (LaLu) 3-x-y Sm x Gd y Fe 5-z Ga z O 12 , wherein: 0.3≦x≦1.0; 0.2≦y≦1.0; and 0.0≦z≦0.8, said substrate being a single-crystalline substrate of Gd 3 Ga 5 O 12 , and said garnet film being epitaxially grown on the (111) surface of the single-crystalline substrate of Gd 3 Ga 5 O 12 .
Claim 2
Dependent Claim
81 words
A garnet film on a substrate, for a magnetic bubble element, said garnet film having such a composition as is expressed by a general formula of (LaLu) 3-x-y Sm x Gd y Fe 5-z Ga z O 12 , wherein: 0.3≦x≦1.0; 0.2≦y≦1.0; and 0.0≦z≦0.8, said substrate being a single-crystalline substrate of Gd 3 Ga 5 O 12 , and said garnet film being epitaxially grown on the (111) surface of the single-crystalline substrate of Gd 3 Ga 5 O 12 .
Claim 3
Dependent Claim
25 words
A garnet film on a substrate as set forth in claim 1, wherein said garnet film has a thickness of about 10 to 0.3 μm.
Claim 4
Dependent Claim
19 words
A garnet film on a substrate as set forth in claim 2, wherein the film thickness is 2.5-0.3 μm.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-08 | 1987-02-07 | 1987-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-08 | 1991-02-07 | 1991-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-08 | 1995-02-07 | 1995-08-09 | $7700.00 | Window Closed / Lapsed |