Talk:Delta potential barrier (QM)

I already created an image to explain the notation but think the quality of it could be vastly improved. It would be good if somebody could check the equations and English as well. Bamse 10:59, 28 July 2006 (UTC)

I think I found an error
There is a phase shift of pi in a reflection from a delta potential.

Take the equation Ar+Al=Br+Bl. With the identifications with the transmission and reflection coefficients made later in the article this becomes 1+r=t or t-r=1 which is clearly not right.

If you howerver include the phase shift in your initial equations the Al part gets a minus sign (that all that changes) and you get the correct equation r+t=1 for a lossless reflector. This would of course also effect the final results for r and t. The results I have here are from an exam problem. They use a somewhat different notation. I may correct the article myself when I come here again but I don't have time now. Please comment here if you think I'm wrong.

Andreas 68.35.63.164 03:44, 24 December 2006 (UTC)


 * I am not sure I understand what you mean, but please note that small r,t are amplitudes which generally don't satisfy (need not satisfy) r+t=1. On the other hand, capital R,T are the probabilities for transmission and reflection and do satisfy R+T=1. Bamse 07:14, 9 January 2007 (UTC)