US4255465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing Josephson-effect junctions
Assignee: Commissariat à l'Énergie Atomique et Aux Énergies Alternatives
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Filing: 1974-08-20
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Granted: 1981-03-10
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Expires: 1994-08-20
Abstract
Abstract This invention relates to a method of producing a Josephson-effect superconductive junction. The method is characterised in that a superconductive refractory material is applied as a thin and uniform deposit to an insulating substrate, the deposit is defined to give it the form of a bridge between two studs of greater width than the said bridge, and in that the junction at very low temperature is subjected to at least one current pulse, the intensity and duration of which have a value dependent upon the required critical Josephson current. A particular application of the invention is the production of a magnetometer.
Inventors
- 👤 Paul Bernard
- 👤 Daniel Zenatti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:51
CPC Classifications
H; H10; H10N; H10N60/00; H10N60/01; H10N60/0912; Y; Y10; Y10S; Y10S505/00; Y10S505/80; Y10S505/815; Y10S505/818; Y10S505/819; Y10S505/825; Y10S505/917; Y10S505/922; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49014
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
114 words
A method of producing Josephson-effect junctions characterised in that a thin and uniform deposit of a superconductive refractory material is made on an insulating substrate, the said deposit is defined to give it the shape of a bridge between two studs of greater width than said bridge, and the said junction at a very low temperature is then subjected to at least one current pulse to change the said deposit from a condition in which said deposit does not exhibit the Josephson-effect to a condition in which said deposit exhibits the Josephson effect, said bridge having dimensions such that prior to application of said current pulse said deposit does not exhibit the Josephson effect.
Claim 2
Independent Claim
114 words
A method of producing Josephson-effect junctions characterised in that a thin and uniform deposit of a superconductive refractory material is made on an insulating substrate, the said deposit is defined to give it the shape of a bridge between two studs of greater width than said bridge, and the said junction at a very low temperature is then subjected to at least one current pulse to change the said deposit from a condition in which said deposit does not exhibit the Josephson-effect to a condition in which said deposit exhibits the Josephson effect, said bridge having dimensions such that prior to application of said current pulse said deposit does not exhibit the Josephson effect.
Claim 3
Dependent Claim
20 words
A method according to claim 1, characterised in that the bridge has a width contained between 5 and 30 microns.
Claim 4
Dependent Claim
30 words
A method according to claim 1, characterised in that the superconductive material is niobium which is vacuum-deposited by evaporation, the substrate being kept at a temperature of about 400° C.
Claim 5
Dependent Claim
25 words
A method according to claim 1, characterised in that after deposition of superconductive material a layer of conductive metal is deposited over the superconductive material.
Claim 6
Dependent Claim
37 words
A method according to claim 1, characterised in that the deposit of superconductive material and the metal deposit are defined by photomasking and chemical etching so that the metal deposited is left only at two electrical contacts.
References Cited (Backward Citations)
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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) | 1984-03-09 | 1984-09-08 | 1985-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-09 | 1988-09-08 | 1989-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-09 | 1992-09-08 | 1993-03-10 | $7700.00 | Window Closed / Lapsed |