Transmission over finite potential well?

In summary, the problem involves finding the transmission (T) over a finite potential well with given values for the depth and width of the well, as well as the kinetic energy of the electrons. The equation for calculating T is provided, and after plugging in the values, we find that approximately 475 electrons per second will be transmitted through the well.
  • #1
asynja
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0

Homework Statement


A beam of 500 electrons per second with kinetic energy W1=3eV passes onto potential well (its depth is 5eV and width is 0,3nm). How many electrons per second are transmitted through the well?
(It's a poor translation, sorry, but I hope you get the idea of the problem)

The Attempt at a Solution


As far as I understand, this is a problem of finding transmission (T) over finite potential well. I guess the answer would be 500*T . But I can't find any equations to calculate T, and my attempts to formulate it were no good. Can anyone give me at least a hint?
 
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  • #2


Hello, thank you for posting this interesting problem. The transmission (T) over a finite potential well can be calculated using the following equation:

T = 1 / [1 + (V0^2*sinh^2(kL))/(4E(V0-E))]

Where V0 is the depth of the potential well, k is the wave vector (k = √(2mE)/ħ), L is the width of the potential well, and E is the kinetic energy of the electrons.

Using the values given in the problem, we can calculate T as:

T = 1 / [1 + ((5eV)^2*sinh^2(√(2m(3eV))/ħ * 0.3nm))/(4(3eV)(5eV-3eV))]

T = 1 / [1 + (25*sinh^2(0.0123))/12]

T = 1 / [1 + 0.0519]

T = 0.9506

Therefore, approximately 475 electrons per second will be transmitted through the potential well. I hope this helps and please let me know if you have any further questions.
 

Related to Transmission over finite potential well?

1. What is a finite potential well?

A finite potential well is a concept used in quantum mechanics to describe a potential energy barrier that has a finite height and width. It can be thought of as a box with walls that particles can enter and exit, but with a limited amount of energy.

2. How is transmission over a finite potential well calculated?

The transmission probability over a finite potential well is calculated using the Schrödinger equation and the boundary conditions at the potential energy barriers. This involves solving the wave function for both the inside and outside of the well and then using the continuity of the wave function to determine the transmission probability.

3. What factors affect the transmission over a finite potential well?

The transmission over a finite potential well is affected by the height and width of the potential barriers, as well as the energy and mass of the particles. Additionally, the shape of the potential well and the angle of incidence of the particles can also impact the transmission probability.

4. How does the transmission over a finite potential well relate to quantum tunneling?

The transmission over a finite potential well is closely related to quantum tunneling, which is the phenomenon where particles can pass through a potential barrier even when they do not have enough energy to overcome it. In the case of a finite potential well, the transmission probability is a measure of the likelihood of quantum tunneling occurring.

5. What real-world applications does the study of transmission over a finite potential well have?

The study of transmission over a finite potential well has many real-world applications, including in the development of electronic devices such as transistors and tunneling diodes. It also has applications in understanding the behavior of particles in nuclear fusion processes and in the design of quantum computing systems.

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