1. The problem statement, all variables and given/known data Consider particles incident on a potential energy step with E<U. (That is, a particle with total energy E travels along one dimension where U=0, then crosses, at point x=0 into a region where U>E.) (The particle is incident on the potential energy step from the negative x direction.) Starting with the wave functions, x < 0: Ψ0 = A’e^(ikx) + B’e^(-ikx), k = 2mE/h_bar2 x >= 0: Ψ1 = Ce^(k1x) + De^(-k1x), k1 = 2m(U-E)/h_bar2 Apply the boundary conditions for Ψ and dΨ/dx and show that the full wave intensity is reflected at the step [i.e., |A'|^2 = |B'|^2]. 2. Relevant equations Ψ0(x=0) = Ψ1(x=0) dΨ0(x=0)/dx = Ψ1(x=0)/dx 3. The attempt at a solution I set C=0, or else the wave function Ψ1 may become infinity. The boundary conditions are stated above. They become A' + B' = D and ikA' - ikB' = -k1D How, from this, do I find that |A'|^2 = |B'|^2 ? Thanks.