A Why the physical meaning of the quantum Hall effect is important

skyhj105
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I have read some paper about transport measurement of graphene.
From classical hall effect, we can get some information about kind of charge carrier, charge density etc.
So, it is important for understanding matter.
But, I don`t know why quantum hall effect is important in graphene transport measurement.
It`s consequence is just a quantization of conductance and by this quantization, we can conclude this electronic system is just a 2D.
 
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skyhj105 said:
But, I don`t know why quantum hall effect is important in graphene transport measurement.
It`s consequence is just a quantization of conductance and by this quantization, we can conclude this electronic system is just a 2D.

Because I) it tells us quite a lot about the materials and II) graphene can be used to make a quantum Hall resistance standard, so it is an important application (it is still not used routinely, but that will happen quite soon)
 
f95toli said:
Because I) it tells us quite a lot about the materials and II) graphene can be used to make a quantum Hall resistance standard, so it is an important application (it is still not used routinely, but that will happen quite soon)
First of all, Thank you for your reply.
But your answer is too abstract for me to understand. Can you give me a example of property judged by quantum hall effect?
 
graphene is a 2-d system, the quantum Hall effect becomes extremely important.
 
Dr Transport said:
graphene is a 2-d system, the quantum Hall effect becomes extremely important.
The reason why it is important is that it is a evidence of 2D electronic structure. Is it right? and That`s all?
 
skyhj105 said:
The reason why it is important is that it is a evidence of 2D electronic structure. Is it right? and That`s all?

It is not clear to me what you are actually asking.
*Are you wondering why there is so much interest in the QHE in graphene?
*Are you wondering what you can learn from measurements of the QHE in graphene?

The two questions are of course related, but the main answer to the first questions is that QHE based resistance standards is an important -practical- application of graphene; if it wasn't for this fact there wouldn't be nearly as much interest in this topic.
 
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