US3879715A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Damped josephson junction memory cell with inductively coupled resistive loop
Assignee: International Business Machines Corp
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Filing: 1973-12-28
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Granted: 1975-04-22
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Expires: 1993-12-28
Abstract
Abstract A memory cell comprising at least one Josephson junction is properly damped for effective operation by inductively coupling a resistive loop to the memory cell. The resistive loop may be located in the vicinity of the vertical projection of the memory cell so as to not affect the packing of a plurality of memory cells.
Inventors
- 👤 Hans H Zappe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:01
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/44; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/831; Y10S505/832
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
79 words
A memory cell comprising a superconducting first loop with at least one Josephson device therein, said loop having an equivalent circuit comprising a parallel combination of a resistor Rj, a capacitor C and an inductance L, wherein Rj > 1/2 square root L/C, and a second loop including resistive means, said second loop in flux-coupling relation to said first loop to provide an effective equivalent resistance in said first loop which is < OR = 1/2 square root L/C.
Claim 2
Dependent Claim
79 words
A memory cell comprising a superconducting first loop with at least one Josephson device therein, said loop having an equivalent circuit comprising a parallel combination of a resistor Rj, a capacitor C and an inductance L, wherein Rj > 1/2 square root L/C, and a second loop including resistive means, said second loop in flux-coupling relation to said first loop to provide an effective equivalent resistance in said first loop which is < OR = 1/2 square root L/C.
Claim 3
Dependent Claim
79 words
A memory cell comprising a superconducting first loop with at least one Josephson device therein, said loop having an equivalent circuit comprising a parallel combination of a resistor Rj, a capacitor C and an inductance L, wherein Rj > 1/2 Square Root L/C, and a second loop including resistive means, said second loop in flux-coupling relation to said first loop to provide an effective equivalent resistance in said first loop which is < or = 1/2 Square Root L/C.
Claim 4
Dependent Claim
79 words
A memory cell comprising a superconducting first loop with at least one Josephson device therein, said loop having an equivalent circuit comprising a parallel combination of a resistor Rj, a capacitor C and an inductance L, wherein Rj > 1/2 Square Root L/C, and a second loop including resistive means, said second loop in flux-coupling relation to said first loop to provide an effective equivalent resistance in said first loop which is < or = 1/2 Square Root L/C.
Claim 5
Dependent Claim
21 words
The apparatus of claim 1 in which said first and second loops are located in first and second spaced planes respectively.
Claim 6
Dependent Claim
17 words
The apparatus of claim 1 in which said second loop comprises non-superconductive material at said operating temperature.
Claim 7
Dependent Claim
26 words
The apparatus of claim 1 in which said second loop is located in a plane between the plane of said first loop and a ground plane.
Claim 8
Dependent Claim
26 words
The apparatus of claim 1 in which said first loop is located in a plane between the plane of said second loop and a ground plane.
Claim 9
Dependent Claim
17 words
The apparatus of claim 1 in which said first loop has at least one Josephson device therein.
Claim 10
Dependent Claim
19 words
The apparatus of claim 1 in which R 1/2 Square Root L/C whereby said memory cell is critically damped.
Claim 11
Dependent Claim
19 words
The apparatus of claim 1 in whch R < 1/2 Square Root L/C whereby said memory cell is overdamped.
Claim 12
Dependent Claim
27 words
The apparatus of claim 1 in which said first loop occupies an area A1 and said second loop occupies an area A2, where A1 not = A2.
Claim 13
Dependent Claim
10 words
The apparatus of claim 9 in which A1 > A2.
Claim 14
Dependent Claim
29 words
The apparatus of claim 9 in which said first loop lies in a first plane and said second loop lies in a second plane parallel to said first plane.
Claim 15
Dependent Claim
18 words
The apparatus of claim 1 which includes an insulating layer between said first loop and said second loop.
Claim 16
Dependent Claim
54 words
A memory cell which is properly damped for effective operation and which comprises a plurality of components deposited in separate layers overlying each other, said components including, a substrate, a superconducting ground plane deposited on said substrate, a loop of normal material, and a superconductive memory loop including at least one Josephson device therein.
Claim 17
Dependent Claim
54 words
A memory cell which is properly damped for effective operation and which comprises a plurality of components deposited in separate layers overlying each other, said components including, a substrate, a superconducting ground plane deposited on said substrate, a loop of normal material, and a superconductive memory loop including at least one Josephson device therein.
Claim 18
Dependent Claim
24 words
The memory cell of claim 13 in which said loop of normal material is deposited above said ground plane and below said memory loop.
Claim 19
Dependent Claim
24 words
The memory cell of claim 13 in which said memory loop is deposited above said ground plane and below said loop of normal material.
Claim 20
Dependent Claim
20 words
The memory cell of claim 13 in which said loop of normal material is inductively coupled to said memory loop.
References Cited (Backward Citations)
US3705393A
Cited
US3764905A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-21 | 1978-10-21 | 1979-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-21 | 1982-10-21 | 1983-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-21 | 1986-10-21 | 1987-04-22 | $7700.00 | Window Closed / Lapsed |