High frequency operation of JTL ring oscillator with a passive transmission line

Author

Suzuki, Hideo ; Nagasawa, Shuichi ; Hasegawa, Haruhiro ; Hashimoto, Tatsunori ; Miyahara, Kazunori ; Enomoto, Youichi

Author_Institution

Supercond. Res. Lab., ISTEC, Tokyo, Japan

Volume

11

Issue

1

fYear

2001

fDate

3/1/2001 12:00:00 AM

Firstpage

1082

Lastpage

1085

Abstract

We have designed ring oscillators to test rapid single flux quantum (RSFQ) circuits with passive transmission lines at high frequencies. To reduce the width of the transmission line, design methods for increasing the characteristic impedance of the transmission line have been investigated and then we designed a 5-stage of Josephson transmission line (JTL) receiver which can transform the impedance from 1 to 4 Ω by changing the critical current and the inductance. The receiver, driver, and micro-strip line were inserted in a ring oscillator. The ring oscillator fabricated with the Nb/AlOx/Nb junction process was successfully operated at frequencies ranging from 6 to 10 GHz for line lengths of 0.6, 3, 6, and 9 mm. The usefulness of the impedance transformation was then confirmed experimentally. A propagation delay per unit length of 8.4 ps/mm was also obtained

Keywords

microwave oscillators; superconducting integrated circuits; superconducting microwave devices; superconducting transmission lines; 6 to 10 GHz; Josephson transmission line; Nb-AlO-Nb; Nb/AlOx/Nb junction; critical current; driver; high frequency operation; impedance transformation; inductance; microstrip line; passive transmission line; propagation delay; rapid single flux quantum circuit; receiver; ring oscillator; Circuit testing; Critical current; Design methodology; Distributed parameter circuits; Frequency; Impedance; Inductance; Niobium; Propagation delay; Ring oscillators;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.919535

Filename

919535