Electrical and noise properties of YBa/sub 2/Cu/sub 3/O/sub 7/ ramp-type Josephson junctions

Author

Schilling, M.

Author_Institution

Inst. fur Angewandte Phys., Hamburg Univ., Germany

Volume

7

Issue

2

fYear

1997

fDate

6/1/1997 12:00:00 AM

Firstpage

2960

Lastpage

2963

Abstract

Josephson junctions with PrBa/sub 2/Cu/sub 3/O/sub 7/ barriers are used in integrated magnetometers, where for biomagnetic applications the noise at low frequencies should be as low as possible. The 1/f-noise contribution close to the critical current is governed by critical current fluctuations. We measure the electrical and noise properties of our ramp-type Josephson junctions and interpret them in a model of resonant tunneling through the PrBa/sub 2/Cu/sub 3/O/sub 7/ barrier. We find that the critical current fluctuations /spl delta/I/sub c//I/sub c/ scale with the temperature dependent critical current. The consequences for the noise properties of integrated magnetometers are discussed.

Keywords

1/f noise; Josephson effect; SQUID magnetometers; barium compounds; critical current density (superconductivity); current fluctuations; fluctuations in superconductors; high-temperature superconductors; superconducting device noise; superconductive tunnelling; yttrium compounds; 1/f noise; PrBa/sub 2/Cu/sub 3/O/sub 7/; PrBa/sub 2/Cu/sub 3/O/sub 7/ barrier; YBa/sub 2/Cu/sub 3/O/sub 7/; YBa/sub 2/Cu/sub 3/O/sub 7/ ramp-type Josephson junction; biomagnetic application; critical current fluctuations; electrical properties; integrated magnetometer; low frequency noise; resonant tunneling; Acoustical engineering; Biomagnetics; Critical current; Electric variables measurement; Fluctuations; Frequency; Josephson junctions; Low-frequency noise; Magnetometers; Noise measurement;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.621935

Filename

621935