New Exponent for the Nonlinear<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi mathvariant="italic">IV</mml:mi></mml:math>Characteristics of a Two Dimensional Superconductor

Abstract

The exponent $a$ for the nonlinear $\mathrm{IV}$ characteristics, $V\ensuremath{\sim}{I}^{a}$, is obtained from a critical scaling argument for a two dimensional superconductor below ${T}_{c}$. The scaling assumption is supported by numerical simulations. The $\mathrm{IV}$ characteristics for the resistively shunted-juction model is simulated numerically, and excellent agreement with the predicted exponent is found. The new scaling exponent differs from the generally accepted Ambegaokar-Halperin-Nelson-Siggia result. The reason for this discrepancy is discussed.