Chaos and noise in Josephson tunnel junctions
John L. Clarke, Robert F. Miracky, John M. Martinis, R. H. Koch · eScholarship (California Digital Library) · 1983
The current-voltage characteristics of Josephson 'tunnel junctions shunted by a conductance with substantial self-inductance exhibit regions of stable negative resistance.At certain values of bias current, the junctions exhibit chaos, which is manifested as a low frequency voltage nOise•equivalent to a noise temperature of about 103K.At other bias points, switching between subharmonic modes or between a subharmonic mode and a chootic regime produces low frequency noise with 0' noise temperature often ex"" ceeding 106K.Analog simulations indicate that, at least under some conditions, the switching is induced by intrinsic thermal noise.The analog has also been used to show that switching induced by thermal noise is responsible for the noise rise observed experimentally in three-photon Josephson' ,parametric amplifiers.'.