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Griffiths QM 2.33 Solution: Transmission and reflection Coefficient for Step Potential Barrier

In this video I will solve problem 2.33 as it appears in the 3rd edition of Griffiths Introduction to Quantum Mechanics. The problem asks us to consider the Step function potential and calculate the reflection coefficient for the case E greater than V0 and E smaller than V0. We then need to consider that for a potential such as this that does not go back to zero to the right of the barrier, the transmission coefficient is not simply |F|**2/|A|**2, with A the incident amplitude and F the transmitted amplitude, because the transmitted wave travels at a different speed. Finally, we check that T+R=1 My name is Nick Heumann, I am a recently graduated physicist. I love to teach physics, so I decided to give YouTube a try. English is not my first language, but I hope that you can understand me well enough regardless. ▬ Contents of this video ▬▬▬▬▬▬▬▬▬▬ 00:00 Introducing the problem 02:00 Explaining the procedure for solving problems like this 02:47 a) Building the wavefunction 05:30 a) Apply border conditions 06:30 a) Solving the system for R 09:00 b) Building the wavefunction 12:15 b) Apply border conditions 13:00 b) Solving the system for R 17:32 c) Find the new expression for T 20:38 d) Finding transmission coefficient T