Temperature dependence of a high-Tc single-flux-quantum logic gate up to 50 K
Kazuo Saitoh, Tadashi Utagawa, Youichi Enomoto
Basic characteristics of a simple single-flux-quantum (SFQ) logic gate using high-Tc material and Josephson junction (NdBa2Cu3O7−δ and focused ion beam junction) have been investigated. The logic gate consists of an rf-superconducting quantum interference device (rf-SQUID) and a dc-SQUID. In the logic gate, elementary SFQ logic operations, such as generating SFQ (dc/SFQ) and providing simultaneous readout (SFQ/dc), have been confirmed up to 50 K. The temperature dependencies of the output voltage level and the critical current-normal resistance (IcRn) product were compared, and the decreasing tendency of the output voltage level for increasing temperature was found to be more rapid than that of the IcRn product.
Applied Physics Letters•May 25, 1998•11 citations