We perform Langevin dynamic simulations to calculate the current-voltage (I-V) characteristics for anisotropic three-dimensional arrays of resistively shunted Josephson junctions as a high-${\mathit{T}}_{\mathit{c}}$ oxide model. In zero and finite applied magentic fields, at various Josephson-coupling anisotropies (γ=${\mathit{J}}_{\mathrm{\Vert }\mathrm{\Vert }\mathit{c}}$/${\mathit{J}}_{\mathrm{\perp }\mathit{c}}$), we see that the interlayer Josephson coupling gives rise to a nonvanishing critical current (${\mathit{I}}_{\mathit{c}}$), and the low-temperature phase displays non-Ohmic power-law I-V characteristics [V∝I(I-${\mathit{I}}_{\mathit{c}}$${)}^{\mathrm{\alpha }\mathrm{-}1}$]. Based on the γ dependence of ${\mathit{I}}_{\mathit{c}}$, we discuss the two- to three-dimensional crossover associated with thermal excitations of vortex-antivortex pairs.

• Received 13 May 1993

DOI:https://doi.org/10.1103/PhysRevB.48.13784