High-density ndro sfq josephson interferometer memory cell

A new Single Flux-Quantum (SFQ) Nondestructive Read-Out (NDRO) random-access asymmetric 2-Joseph-son-junction interferometer memory cell with only one control line has been investigated and designed. The binary information is stored in the cell nonvolatilely without a bias current. For random access, this is the first known interferometer memory cell without a diagonalline. Therefore, this NDRO SFQ memory cell leads intrinsically to smaller cell area and simpler decoder schemes. A cell design of only 52 lithographic squares is given to demonstrate the potential for high-density memory chips. Wide nominal read and write operating margins are obtained. The NDRO interferometer memory cell proposed is promising for use in a high-performance Josephson computer. © 1981 IEEE