The Electromagnetic Waves, Beam Envelopes Interface has these domain, boundary, edge, point, and pair nodes available from the
Physics ribbon toolbar (Windows users),
Physics context menu (Mac or Linux users), or right-click to access the context menu (all users).
For the unidirectional formulation, the electric field is given by the product of the electric field envelope E1 and the phase function (see
Wave Vectors). Because
E1 is being solved for and the phase function is continuous across boundaries, the tangential component of the electric field is always continuous, and thus the first condition is automatically fulfilled. The second condition is equivalent to the natural boundary condition for the unidirectional formulation