Application of Josephson junctions to computer storage and logic elements and two magnetic measurements

Conference · Wed Dec 31 23:00:00 EST 1975 · AIP (Am. Inst. Phys.) Conf. Proc.; (United States)

OSTI ID:7361530

Clarke, J

The dc and ac Josephson effects and the behavior of the current-voltage characteristics of Josephson junctions are briefly reviewed. The Josephson junction cryotron is described. Two cryotrons have been incorporated into a NDRO memory cell with a switching time of 80ps, a power-delay product of 10/sup -16/J, and an area of 900..mu..m/sup 2/ DRO memory cells involving the storage of a single flux quantum have estimated switching speeds of 50ps and a dissipation in continuous operation of 40nW. Latching logic elements with a switching time of 200ps and a power-delay product of 5fJ have been built. Non-latching devices and the flux shuttle are described. The use of dc and rf SQUIDs in conjunction with flux transformers for magnetic measurements is discussed. Presently achieved sensitivities are: magnetic field, 10/sup -15/THz/sup -//sup /sup 1///sub 2//, magnetic field gradient, 10/sup -13/Tm/sup -1/Hz/sup /sup -1///sub 2//; magnetic susceptibility, 2 x 10/sup -11/ e.m.u. for lcm/sup 3/ at 10/sup -1/T; voltage, 10/sup -15/VHz/sup /sup -1///sub 2//. The highest energy resolution reported for a SQUID-transformer combination is 8 x 10/sup -30/JHz/sup -1/ in a frequency range from 2 x 10/sup -2/ Hz to 1 kHz. At lower frequencies the noise power spectrum is 1/f. The performance of the computer and measuring devices is compared with that of conventional (non-superconducting) devices.

• Research Organization: Univ. of California, Berkeley
• OSTI ID: 7361530
• Journal Information: AIP (Am. Inst. Phys.) Conf. Proc.; (United States), Journal Name: AIP (Am. Inst. Phys.) Conf. Proc.; (United States) Vol. 29; ISSN APCPC
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
CRYOTRONS
ELECTRICAL PROPERTIES
ELECTRONIC CIRCUITS
JOSEPHSON EFFECT
JOSEPHSON JUNCTIONS
LOGIC CIRCUITS
MAGNETOMETERS
MEASURING INSTRUMENTS
MEMORY DEVICES
PHYSICAL PROPERTIES
SUPERCONDUCTING DEVICES
SUPERCONDUCTING JUNCTIONS
USES