- #1

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I thought that meant that there was a small probability of detecting an electron within the barrier. But the reflection coefficient of the probability current is unity. So what’s going on here?

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- Thread starter Sacroiliac
- Start date

- #1

- 13

- 1

I thought that meant that there was a small probability of detecting an electron within the barrier. But the reflection coefficient of the probability current is unity. So what’s going on here?

- #2

- 80

- 0

For a very wide barrier, the inverse if the transmission coefficient (T) goes to infinity, so T --> 0 and R --> 1, like you said. The probabilty density of the wavefunction does decay exponentially within the barrier, but the amplitude decreases as the width of the barrier increases. So, for a very wide barrier, the probability amplitude inside the barrier would be extrememly small. If we take the extreme case where R = 1, then the probability amplitude would basically be zero.

Here is a Shockwave movie that might help. Modify the width, and watch the behavior of the probability density.

http://phys.educ.ksu.edu/vqm/html/qtunneling.html

Here is a Shockwave movie that might help. Modify the width, and watch the behavior of the probability density.

http://phys.educ.ksu.edu/vqm/html/qtunneling.html

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