Potential Barrier (Q.M. vs Classical Phy.)

[n0_3sc]

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]

That's correct.

 

[n0_3sc]

Cool thanks.

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

 

[Meir Achuz]

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.