  The effect of temperature on the form of discrete changes in the current in
highly inductive (~10-6 H) doubly-connected superconductors with
niobium-niobium clamped point contacts is determined experimentally. The
magnitude and duration of the voltage pulse on a doubly-connected
superconductor is measured at the time of the discrete change in its current
state. The pulse magnitude is close to the energy gap 2D/e of the
superconductor and its duration (~10-6 s) corresponds to the minimum possible
time (~10-12 s) for a change in the state of the contact when the depairing
current through it is reached. The measurement data are discussed in terms of
models of the quantum interference of currents in a doubly-connected
superconductor with clamped point contacts in the form of a quantum
interferometer.
