Dynamic properties of variable thickness bridges

We investigate the time-dependent behaviour of the variable-thickness bridges (VTB) and give expressions for the excess current, for the
V \cos \varphi
term and for the upper frequency boundary of the Josephson effect. We discuss the validity of the results obtained for different weak links: cross-scribed bridges, proximity effect bridges and whiskers. On the basis of previous analysis the properties of memory element QUANTRON are studied. Then it is shown that the properties of many-terminal bridges allow one to combine high parameters of an externally-pumped down-converter and the simplicity of a self-pumped down-converter.