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View Full Version : Potential Barrier (Q.M. vs Classical Phy.)


n0_3sc
Mar16-07, 10:29 PM
If you have a Potential Barrier V (width a) and particles incident on left with energy E where E>V, are the following true:

Classical Physics:
- All particles will be transmitted past the barrier
- It cannot be reflected because that would mean it has negative E which is not possible.

Quantum Mecahnically:
- Some particles will be reflected (due to there wave nature)
- Some particles will be transmitted
- Some particles may exist in the barrier.

Am I missing anything important?

vanesch
Mar17-07, 02:25 AM
That's correct.

n0_3sc
Mar17-07, 02:27 AM
Cool thanks.

To be sure, quantum mechanically a particle is allowed to EXIST in the barrier itself?

Meir Achuz
Mar17-07, 09:28 AM
Cool thanks.

To be sure, quantum mechanically a particle is allowed to EXIST in the barrier itself?
No, not inside the wall itself.
Just as in the classical case, if the wall is between x=0 and x=a, a particle will be in the region 0<x<a for a short period of time.