Hence, ik−[ψ+(xa)−ψ−(xa)]=ik+[ψ+(xb)−ψ−(xb)]. These two equations can be combined into a single matrix equation: \[\begin{bmatrix}1 & 1 \\ k...Hence, ik−[ψ+(xa)−ψ−(xa)]=ik+[ψ+(xb)−ψ−(xb)]. These two equations can be combined into a single matrix equation: [11k−−k−][ψ+(xa)ψ−(xa)]=[11k+−k+][ψ+(xb)ψ−(xb)]. After doing a matrix inversion, this becomes \[\Psi_b = \mathbf{M}_s(k_+,k_-) \, \Psi_a, \;\;\;\mathrm{where}\…
