Dc SQUID based on unshunted Josephson junctions: experimental results

摘要: It has been proposed that a new SQUID type be constructed by using unshunted Josephson junctions instead of resistively shunted junctions. Using this approach we are able to present having high output dynamic resistance and device characterized negative an extremely low noise. The first mentioned is called high-gain SQUID, the latter SQUID. This article describes preliminary experiments obtained from SQUIDs based on concept. iv characteristics shown resemble theoretically predicted but noise performance was higher than expected. Most likely reason for imperfect damping in frequencies near 1 GHz. >