Semiconductor has electron and hole, why not conductor has hole?

[Outrageous]

For intrinsic semiconductor, the know its conductivity=2 neμ , where his the number of electron per cubic meter, e is the charge of an electron, μ is the electron mobility.
But if I want to calculate the conductivity of a conductor= neμ.
Why not consider the hole in? Electron leaves its original place to conduction band will leave a hole behind, this is not true in conductor?

Thank you.

 

[Fightfish]

The electrons in conductors responsible for electrical conduction are already in the conduction band even at 0K (ie the Fermi level is in the conduction band). That's why we call them "conductors" to begin with.

 

[Outrageous]

Thank you^^

 

[olaney]

Some do

Some conductors, like tin, do support hole conduction. They are termed semimetals. The classic semimetallic elements are arsenic, antimony, bismuth, α-tin (gray tin) and graphite, an allotrope of carbon. http://en.wikipedia.org/wiki/Semimetal

 

[sardar]

I appreciate your curiosity and interest in understanding the concept of conductivity in semiconductors and conductors.

To answer your question, it is important to first understand the fundamental difference between semiconductors and conductors. In semiconductors, the valence band (the highest energy band occupied by electrons) and the conduction band (the lowest energy band available for electrons to move into) are separated by a small energy gap. This gap is small enough that at room temperature, some electrons can acquire enough energy to jump from the valence band to the conduction band, creating a flow of charge and allowing the material to conduct electricity.

On the other hand, in conductors, the valence and conduction bands overlap, meaning that the electrons are free to move throughout the material, resulting in a high conductivity. In this case, there is no need to consider holes because the electrons themselves are responsible for conducting electricity.

In semiconductors, the concept of holes arises due to the movement of electrons from the valence band to the conduction band. When an electron moves, it leaves behind a positively charged "hole" in the valence band. This hole can then be filled by another electron, creating a chain reaction and contributing to the flow of charge.

However, in conductors, the overlapping of the valence and conduction bands means that there are no distinct energy levels for electrons to jump to. Therefore, there is no need to consider holes in the calculation of conductivity.

In summary, the presence of holes is a unique characteristic of semiconductors, and it is not applicable to conductors. The conductivity of a conductor can be accurately calculated using the formula neμ, which takes into account the number of electrons and their mobility. I hope this explanation helps clarify the concept for you. Keep asking questions and exploring the world of science!