Question

In: Physics

1. Calculate the permeability of electrons with energy of 0.1 eV and 0.5 eV respectively when...

1. Calculate the permeability of electrons with energy of 0.1 eV and 0.5 eV respectively when penetrating a positional energy barrier of 1.0 eV in height and 100 pm in length by tunnel phenomenon.
k Attachment image=[2m(V-E)]^1/2
T={1+(e^kL-e^-kL)^2/16ε(1-ε)}^-1 (ε= E/V)
2. Explain the meaning of tunneling covered in the above problem with the wave and explain the difference between classical and quantum mechanics based on it.

Solutions

Expert Solution

Given that

V = 1 eV - height of potential barrier

L - length of potential barrier = 100 pm =

Here

Case 1

case 2

(b)

The process involved here is quantum tunneling.

In case of a potential barrier of barrier potential V and the energy of the particle E, there will be 3 possible scenarios.

E>V

in this case, the particle is a free particle and will go undeviatingly classically and quantum mechanically.

E = V

In this case, the particle will undergo scattering.

E<V

This is the classically forbidden region ie the particle can not cross the barrier in a classical scenario. But quantum mechanically, there is a nonzero probability that the particle can cross through the barrier even if it has less energy. This pheonomena is known as tunneling.


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