RSFQ impulse logic circuitry for future applications in high frequency metrology

At PTB, at a level of medium complexity in superconductor-insulator-superco nductor (SIS) technology, rapid single flux quantum (RSFQ) circuits can be fabricated with a high degree of reproducibility. Their functionality has b een proven up to frequencies higher than 40 GHz. The reliability of circuit operation has been demonstrated by bit error rates of about 10(-16). On th is basis, the RSFQ impulse logic opens up a wide field of digital applicati ons in high frequency (HF) menology. A unique feature to utilize for the ev aluation of microwave systems and equipment is the ability of direct digiti zing of HF signals. Three attractive examples are discussed to apply in the fields of Josephson voltage standards (JVSs) and microwave noise power. Wi th regard to future requirements to operate RSFQ circuits at higher integra tion levels, the possibility of an implementation of intrinsically shunted tunnel junctions as the active circuit elements using superconductor-insula tor-normal conductor-insulator-superconductor (SINIS) technology is discuss ed. (C) 1999 Elsevier Science B.V. All rights reserved.