Difference of the spin Hall effect in intrinsic and extrinsic semiconductors?

In summary, the spin Hall effect is a phenomenon where an electric current induces a spin polarization in a material, leading to a separation of electrons with opposite spins. Intrinsic semiconductors are pure semiconducting materials, while extrinsic semiconductors have impurities intentionally added to modify their electrical properties. In intrinsic semiconductors, the spin Hall effect is primarily caused by spin-orbit coupling, while in extrinsic semiconductors, it is also influenced by impurity scattering. The main factors that affect the spin Hall effect in semiconductors include the material's band structure, spin-orbit coupling strength, impurity concentration, and temperature. Scientists are studying the spin Hall effect in semiconductors through
  • #1
JanSpintronics
32
2
Hello there,

I don't really get the difference between the extrinsic or intrinsic spin hall effect or contribution. As i understand, in extrinsic you have spin scattering by impurities, so its the spin orbit interaction of the spin with its orbit, and this orbit is influenced by an impurity.

In the intrinsic, they say it is also due to spin orbit interaction caused by the bandstructure…but in my opinion its the same as the extrinsic. the bandstructure is also made by impurities. It is meant so, the electron get a transversal component cause of scattering with the "main" atoms?

I also read, intrinsic Spin hall effect is happened DURING sacttering events, so it does not happened in scattering events. But Spin orbit interaction IS scattering (for me all spin orbit interactions do lead to a change in direction). So is that kind of spin orbit interaction in extrinsic and intrinsic different, and if s, where is the difference?

I also read something About the berry face, about and periodic parameter who gives rise to the intrinsic. Should i understand that like an electron which is coming back to its position, so its periodic and then its get , however, a transversal component?

Hope someone can help me,
 
Physics news on Phys.org
  • #2
thanksHello there,

I can definitely understand why the difference between the extrinsic and intrinsic spin hall effect may be confusing. Let me try to clarify it for you.

First, let's start with the extrinsic spin hall effect. As you mentioned, this is caused by spin scattering by impurities. This means that the spin of an electron is affected by the presence of impurities in the material. These impurities can cause the electron's spin to change direction, resulting in a transverse spin current. So, in this case, the spin orbit interaction is due to the impurities in the material.

On the other hand, the intrinsic spin hall effect is caused by the spin orbit interaction within the bandstructure of the material itself. This means that the bandstructure of the material has a built-in spin orbit coupling, which can cause the spin of an electron to change direction and result in a transverse spin current. This is not influenced by impurities, but rather is an inherent property of the material's bandstructure.

Now, you may be wondering, what is the difference between spin orbit interactions in the extrinsic and intrinsic cases? The main difference is that in the extrinsic case, the spin orbit interaction is caused by impurities, while in the intrinsic case, it is caused by the bandstructure of the material itself. In both cases, the spin of the electron is affected, but the underlying cause is different.

Regarding your question about the Berry phase and periodic parameters, these are related to the intrinsic spin hall effect. The Berry phase is a geometric phase that describes the change in a wavefunction as it moves along a closed path in space. This is relevant to the spin hall effect because the spin of an electron can be affected by its path in the material's bandstructure. The periodic parameters refer to the periodicity of the material's bandstructure, which can also affect the spin of an electron and result in a transverse spin current.

I hope this helps clarify the difference between the extrinsic and intrinsic spin hall effect. Let me know if you have any other questions. Happy to help!
 

Related to Difference of the spin Hall effect in intrinsic and extrinsic semiconductors?

1. What is the spin Hall effect?

The spin Hall effect is a phenomenon in which an electric current induces a separation of spin-up and spin-down electrons in a material, resulting in a net spin polarization. This effect is important for spintronics, a field that aims to use the spin of electrons for information processing and storage.

2. What is the difference between intrinsic and extrinsic semiconductors?

Intrinsic semiconductors are pure materials, meaning they have no impurities or defects. Extrinsic semiconductors, on the other hand, have impurities intentionally added to alter their electrical properties. This can include doping with elements such as boron or phosphorus to increase the number of free charge carriers.

3. How does the spin Hall effect differ in intrinsic and extrinsic semiconductors?

In intrinsic semiconductors, the spin Hall effect is primarily driven by spin-orbit coupling, which is the interaction between the spin of an electron and its motion. In extrinsic semiconductors, the effect is also influenced by the impurities present, which can affect the spin-orbit coupling and alter the magnitude of the effect.

4. What are some potential applications of the spin Hall effect in semiconductors?

The spin Hall effect has potential applications in spintronic devices, such as spin valves, which can be used for magnetic sensing and data storage. It can also be used in spin-based logic devices for faster and more energy-efficient computing.

5. Are there any challenges in studying the spin Hall effect in semiconductors?

One challenge in studying the spin Hall effect in semiconductors is the presence of extrinsic effects, such as impurities and defects, which can complicate the interpretation of experimental results. Additionally, the spin Hall effect can be difficult to measure and requires specialized equipment and techniques.

Similar threads

  • Atomic and Condensed Matter
Replies
0
Views
274
  • Atomic and Condensed Matter
Replies
1
Views
2K
  • Atomic and Condensed Matter
Replies
2
Views
2K
  • Atomic and Condensed Matter
Replies
1
Views
1K
  • Atomic and Condensed Matter
Replies
1
Views
2K
Replies
2
Views
2K
Replies
1
Views
1K
  • Atomic and Condensed Matter
Replies
2
Views
4K
  • Atomic and Condensed Matter
Replies
1
Views
4K
  • Electromagnetism
Replies
2
Views
2K
Back
Top