Title :
A subnanosecond clock cryogenic system for Josephson computers
Author :
Kotani, S. ; Inoue, A. ; Suzuki, H. ; Hasuo, S. ; Takenouchi, T. ; Fukase, K. ; Miyagawa, F. ; Yoshida, S. ; Sano, T. ; Kamioka, Y.
Author_Institution :
Fujitsu Lab. Ltd., Atsugi, Japan
Abstract :
Using Josephson chips maintained at 4.4 K by a closed-cycle 3-W desk-size refrigerator, the authors verified the correct operation of a 4-b Josephson microprocessor up to 1.1 GHz. Room temperature and liquid He temperature regions are connected with a 130-ps delay using I/O cables passing through sidewalls of a vacuum vessel. It is proposed that both semiconductor and Josephson devices can coexist on circuit boards that constitute the equivalent of a single board.<>
Keywords :
cryogenics; refrigerators; superconducting processor circuits; 1.1 GHz; 130 ps; 3 W; 4 bit; 4.4 K; Josephson chips; Josephson computers; Josephson devices; Josephson microprocessor; circuit boards; closed cycle desk size refrigerator; liquid He temperature; low temperature package; room temperature package; semiconductor board; subnanosecond clock cryogenic system; vacuum vessel; Cables; Clocks; Cryogenics; Delay; Helium; Microprocessors; Printed circuits; Refrigeration; Superconducting devices; Temperature;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
