I have a question about the implementation of the source term from the Maxwell equation in FDTD Solution. If I choose a electric dipole source, then we can have the following equation:
Now, in FDTD, is the dipole time signal the P_ex term on the right hand side of the equation, or double partial derivative of the P_ex? Also, how does FDTD define the electric dipole? From positive charge to negative or the reverse?
Thank you very much.