Properties of the flux-flow type Josephson oscillator coupled to a quasiparticle detector through a planar stripline cavity are investigated in the millimeter wave region. The present coupling scheme is essential for magnetic field isolation between the oscillator and the Josephson rf-devices, as well as filtering of spurious harmonics.

The minimum current of a two-junction SQUID gate has been studied theoretically. An analytical expression for the current-voltage characteristics of the SQUID gate has been obtained, which includes the minimum current of the SQUID gate. Studies have been made of the dependences of the minimum current on parameters of the SQUID gate such as an interlinked magnetic flux, a loop inductance and a resistance. It is shown that the minimum current of the SQUID gate depends strongly on the interlinked magnetic flux, while it becomes the same as that of a single junction in the absence of the magnetic flux. It is also shown that the obtained analytical results agree well with those of computer simulation.

A new type of Josephson NDRO memory cell is presented, where a sense gate is coupled directly to the memory part, instead of the conventional magnetic coupling scheme. The memory cell operates without complexity of the sequence of signals, and the operation margin is shown to be 20%.

Two-dimensional pattern of an electric potential around a horizontally-placed root of adzuki bean was detected by a multi-electrode measuring system. The vectors of electric current calculated from the electric potential pattern show a long route from the basal part of the root to the apical part.

Dynamic properties of electrical circuits containing a Josephson junction are studied analytically by approximating the sinusoidal current-phase relation by a triangular one. Analytical expressions are obtained for the circuit-parameter dependences of transient voltage waveforms, ac ripples of stationary-state voltage oscillation and minimum currents in several typical circuits, which are shown to be in good agreement with numerical results. It is also shown that these quantities can be well characterized in simple forms in terms of a frequency peculiar to each circuit.