NUMERICAL INVESTIGATION AND MODEL APPROXIMATION FOR THE HYSTERETIC CURRENT-VOLTAGE CHARACTERISTICS OF JOSEPHSON-JUNCTIONS WITH NONLINEAR QUASI-PARTICLE RESISTANCE
Y. Mizugaki et K. Nakajima, NUMERICAL INVESTIGATION AND MODEL APPROXIMATION FOR THE HYSTERETIC CURRENT-VOLTAGE CHARACTERISTICS OF JOSEPHSON-JUNCTIONS WITH NONLINEAR QUASI-PARTICLE RESISTANCE, JPN J A P 1, 36(1A), 1997, pp. 110-113
We present a model analysis for the current-voltage (I-V) characterist
ics of Josephson junctions having superconductor-insulator-superconduc
tor (SIS) structure. The numerical result for the V-m value, which is
the product of the maximum supercurrent and the observed subgap resist
ance, shows a marked decrease with increasing junction critical curren
t density (J(c)). The marked decrease is independent of leak current.
Increasing J(c) reduces the junction capacitance C-J and enlarges the
amplitude of the junction voltage oscillation. Nonlinearity of the qua
siparticle resistance restricts the voltage oscillation amplitude to t
he gap voltage, which results in the rapid decrease of the V-m value.
In this paper, we introduce a sinusoidal oscillation model for the jun
ction voltage, and derive the approximated expressions for the V-m val
ue. The model approximation results agree well with the numerical resu
lts.