Programme

O.11 -- Oral, VCTP-51

Date: Tuesday, 4 August 2026

Time: 08:30 - 08:50

Nonlinear Transport in a One-Dimensional Superconducting Wire within the Time-Dependent Ginzburg–Landau Framework

Le Xuan The Tai, Nguyen Viet Hung, Bui Duc Tinh, Tran Ky Vi

Van Lang University

We investigate the nonequilibrium transport properties of a one-dimensional superconducting wire subjected to a uniform electric field within the framework of the time-dependent Ginzburg–Landau (TDGL) theory. The model incorporates thermal fluctuations through a stochastic noise term satisfying the fluctuation–dissipation relation and is solved numerically using a nonlinear Crank–Nicolson finite-difference scheme combined with Picard iteration. The developed solver is employed to calculate the superconducting order parameter, current density, and electrical conductivity as functions of temperature and applied electric field. The numerical results show that both the superconducting order parameter and conductivity decrease with increasing temperature and field strength, consistent with theoretical expectations near the superconducting transition. In addition, the current–electric-field characteristics exhibit a pronounced nonlinear S-shaped behavior. Comparison between stochastic and deterministic simulations reveals that thermal fluctuations influence the quantitative features of the current response but are not the primary origin of the observed nonlinearity, which persists even in the absence of noise. These findings demonstrate that the proposed numerical framework provides a stable and efficient approach for studying nonlinear transport and fluctuation effects in low-dimensional superconducting systems.

Presenter: Lê xuân Thế Tài