Ⅰ、引言最早用于数字电路的超导器件是1956年由Buok提出的冷子管,它的原理是利用金属从超导态向正常态的转变来执行逻辑功能的。这是一个相变过程,其时间数量级大约是10个毫微秒。由于冷子管的开关速度慢、有功耗,没有得到多大的发展。1965年美国IBM公司开始研究在数字电路中采用约瑟夫森器件,它是利用器件从约瑟夫森隧道效应(导超 I. INTRODUCTION The earliest superconducting device used in digital circuits was the cold tube proposed by Buok in 1956. Its principle is to use the metal to perform the logic function by the transition from superconducting state to normal state. This is a phase change process, which is on the order of 10 nanoseconds. As the cold tube switching speed is slow, there is power, did not get much development. In 1965 the United States IBM company began to study the use of Josephson devices in digital circuits, which is the use of devices from the Josephson tunneling effect