Correction of Numerical Errors in the Charge Conservation Law at Current Sources in Explicit Finite-Difference Time-Domain Method with Higher-Order Accuracy

This study proposes a correction of numerical errors at current sources in the FDTD method with the timedevelopment equations using higher-order differences.Recently, the FDTD methods have been developed by adding odd-degree difference terms to the time-development equations, which relaxes the Courant condition and reduce numerical errors in phase velocity.However, it has been found that there arise large numerical errors in the charge conservation law if the time-development equations including current sources are discretized with higher-order finite differences in space.The numerical errors in the charge conservation law have a negative impact in plasma kinetic simulations.Therefore, corrections of the input current densities are necessary.The numerical errors are suppressed by adding correction terms to the time-development equations of the FDTD methods with higher-order differences.