US3783402A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Josephson junction amplifier
Assignee: United States Department of the Navy
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Filing: 1972-06-28
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Granted: 1974-01-01
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Expires: 1992-06-28
Abstract
Abstract The invention disclosed herein utilizes the Josephson tunneling effect to provide an amplifier having unique characteristics. The Josephson tunneling effect relates to a supercurrent flow thru a thin barrier between two superconductors by quantum mechanical tunneling of electron pairs; in other words, current can flow with no voltage applied between the superconductors. The dc quantum interference effect can produce thru the use of an external magnetic field a large change in barrier current by tunneling and is used herein to produce an amplifier.
Inventors
- 👤 Der Ziel A Van
- 👤 H Choe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:55
CPC Classifications
H; H03; H03F; H03F19/00; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/855
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
115 words
An improved cryogenic amplifier comprising: a. a cryogenic system having a Josephson junction and input and output terminals; b. a bias current supply coupled to said input terminals; c. a source of low frequency signals coupled to said input terminals; d. a pre-amplifier circuit coupled to said output terminals; e. a main amplifier coupled to said pre-amplifier; f. a limiter and frequency modulating discriminator coupled to said main amplifier; g. An attenuator coupled to said limiter and frequency modulating discriminator; h. a low frequency amplifier coupled to said attenuator; i. a bandpass filter coupled to said low frequency amplifier; and, j. means, including an indicating device to show the presence or absence of a signal.
Claim 2
Dependent Claim
115 words
An improved cryogenic amplifier comprising: a. a cryogenic system having a Josephson junction and input and output terminals; b. a bias current supply coupled to said input terminals; c. a source of low frequency signals coupled to said input terminals; d. a pre-amplifier circuit coupled to said output terminals; e. a main amplifier coupled to said pre-amplifier; f. a limiter and frequency modulating discriminator coupled to said main amplifier; g. An attenuator coupled to said limiter and frequency modulating discriminator; h. a low frequency amplifier coupled to said attenuator; i. a bandpass filter coupled to said low frequency amplifier; and, j. means, including an indicating device to show the presence or absence of a signal.
Claim 3
Dependent Claim
15 words
The improved amplifier of claim 1 wherein said Josephson junction is a point contact junction.
Claim 4
Dependent Claim
12 words
The improved amplifier of claim 1 is a thin film sandwich junction.
Claim 5
Dependent Claim
16 words
The improved amplifier of claim 1 wherein said Josephson junction is a thin film bridge junction.
Claim 6
Dependent Claim
16 words
The improved amplifier of claim 1 wherein said Josephson junction is a cross wire type junction.
Claim 7
Dependent Claim
16 words
The improved amplifier of cLaim 1 wherein said Josephson junction is a soder blob type junction.
Claim 8
Dependent Claim
29 words
The improved amplifier of claim 1 wherein said bias current supply of claim 1 which includes a battery in series with a resistance bridge coupled across said input terminals.
Claim 9
Dependent Claim
26 words
The improved amplifier of claim 7 wherein said source of low frequency signals is coupled across a portion of said resistance of said bias current supply.
Claim 10
Dependent Claim
48 words
The improved amplifier of claim 1 wherein said Josephson junction has a cryogenic system which includes a first mounting arm and a second mounting arm, said Josephson junction being mounted on said first and second arms, said arms adjustably mounted for varying the pressure across the Josephson junction.
Claim 11
Dependent Claim
34 words
The device of claim 9 wherein the electrical contacts to said mounting arms is a coaxial member, said mounting system adapted to be maintained at a temperature sufficient to have supercurrent generated by superconductivity.
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) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |