Complementary output switching logic: a superconducting voltage-state logic family operating at microwave frequencies

The development of a new superconducting logic family, complementary output switching logic (COSL), is described. It is described how the two main problems inhibiting superconducting operation at microwave frequencies, namely magnetic flux trapping and large variations of the nominal component values due to the fabrication process, are solved. A brief overview of the operation of the basic logic gate and the layout process is given. Measured results of the basic gates are given for frequencies up to 18 GHz. The measured results of more complex circuits, such as a code converter and a pseudo-random bit sequence generator, are also presented.