ИСТИНА

We develop a design map for navigating the bi-SQUID parameter tradeoffs. Bi-SQUID is a three-junction SQUID combining dc and rf SQUID loops capable of providing highly linear voltage response to the applied magnetic flux. The response linearity can reach 90 to 100 dB with the optimally set parameters including the critical current of the third Josephson junction as the most critical parameter. However to design a bi-SQUID with maximum possible linearity, one ought to take into consideration not only the rf SQUID loop inductance, but also dc SQUID loop inductance and the shared inductance of the loops. The achievable linearity can be degraded from impacts of thermal noise and spread in critical currents. Our experience in bi-SQUID circuit development allows us develop a roadmap for the optimal bi-SQUID design as well as for the design of circuits based on bi-SQUIDs.