Accession Number : AD0670157

Title :   RELAXATION OSCILLATIONS IN JOSEPHSON JUNCTIONS.

Descriptive Note : Rept. for Jun-Oct 67,

Corporate Author : AEROSPACE CORP EL SEGUNDO CALIF LAB OPERATIONS

Personal Author(s) : Vernon,Frank L. , Jr. ; Pedersen,Robert J.

Report Date : FEB 1968

Pagination or Media Count : 21

Abstract : Investigation of the characteristics of Josephson tunneling in tin/tin oxide/tin junctions showed that pulse voltages with sharp rise times were being generated. Pulse amplitude across the junction remained constant and equal to the energy gap voltage V sub g, but pulse frequency could be changed over a 25:1 range by a change in bias voltage from 0 to an upper limit approximately equal to V sub g/2. The oscillation mechanism is that of switching between the pair-current state of the junction at V = 0 and the quasi-particle current state at V = V sub g. The external circuit maintains the switching cycle and determines the output frequency characteristics. Using the L/R time constant of the external circuit and the assumed basic dc I(V) curve of the junction in the absence of relaxation oscillations, calculations were made that accurately describe the observed dc I(V) curves, frequency, and waveforms, including their dependence on bias voltage and magnetic field. (Author)

Descriptors :   (*SUPERCONDUCTORS, *TUNNELING(ELECTRONICS)), ELECTRICAL PROPERTIES, VAPOR PLATING, VACUUM APPARATUS, RELAXATION TIME, OSCILLATION, MAGNETIC FIELDS, TIN, TIN COMPOUNDS, OXIDES

Subject Categories : Electricity and Magnetism
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE