Type II superconductors definition?

In summary, a high temperature superconductor, also known as a Type II superconductor, is a material with a superconducting transition temperature (Tc) higher than 35K. It was originally thought that Tc could not exceed this value based on our understanding of conventional superconductors. However, there are now multiple families of compounds, including the cuprates, ruthenates, and MgB2, that may be considered high-Tc superconductors.
  • #1
Mk
2,043
4
What is the definiton of a high temperature superconductor otherwise known as Type II superconductors?
 
Physics news on Phys.org
  • #2
"What is the definiton of a high temperature superconductor otherwise known as Type II superconductors?"

You need to be a bit careful here. High-Tc superconductors do not have the identical definition as "Type II" superconductors. There are plenty of Type II superconductors that are not high-Tc superconductors. It just happens that all high-Tc superconductors that we have discovered are type II also.

Originally, high-Tc superconductors are the cuprate superconductors first discovered by Bednorz and Mueller. Most people would put Tc of greater than 35K for something to be considered as "high". This number isn't arbitrary. It was originally thought (pre 1986) that this is the upper limit that phonon-mediated superconductivity can get to based on our understanding of conventional superconductors.

Currently, there are several "families" of compounds that may be considered as belonging to the "high-Tc" superconductors, in addition to the cuprates. This includes possibly the ruthenates (even though their Tc's are lower than 35K), and MgB2 compound that was discovered barely 2 years ago.

Zz.
 
  • #3


Type II superconductors are materials that exhibit superconductivity at high temperatures, typically above the boiling point of liquid nitrogen (77 K). They are also known as high temperature superconductors (HTS) and were first discovered in the late 1980s. Unlike Type I superconductors, which completely lose their electrical resistance at a specific critical temperature, Type II superconductors have a mixed state where some of the material remains in the normal state while others exhibit superconductivity. This mixed state allows for higher critical temperatures and stronger magnetic fields to be sustained, making Type II superconductors more practical for real-world applications. The exact definition of a high temperature superconductor varies, but it is generally considered to be any material that exhibits superconductivity above the temperature of liquid nitrogen.
 

1. What is a Type II superconductor?

A Type II superconductor is a material that can conduct electricity with zero resistance at a critical temperature. Unlike Type I superconductors, Type II superconductors have a mixed state where they can partially resist a magnetic field.

2. What is the critical temperature of Type II superconductors?

The critical temperature of Type II superconductors varies depending on the material, but it is generally higher than that of Type I superconductors. It can range from a few degrees above absolute zero to above room temperature.

3. How are Type II superconductors different from Type I superconductors?

Type II superconductors have a mixed state where they can partially resist a magnetic field, while Type I superconductors cannot. Type II superconductors also have a higher critical temperature and can carry higher current densities.

4. What are some examples of Type II superconductors?

Some examples of Type II superconductors include niobium-titanium, niobium-tin, and ceramic materials such as yttrium-barium-copper-oxide (YBCO) and bismuth strontium calcium copper oxide (BSCCO).

5. How are Type II superconductors used in practical applications?

Type II superconductors are used in a variety of practical applications, such as in MRI machines, particle accelerators, and high-speed trains. They are also being researched for use in energy-efficient power transmission and storage systems.

Similar threads

Replies
10
Views
1K
Replies
5
Views
681
Replies
8
Views
661
Replies
2
Views
1K
  • Atomic and Condensed Matter
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
14
Views
942
Replies
2
Views
799
  • Atomic and Condensed Matter
Replies
1
Views
1K
Replies
6
Views
1K
  • Quantum Physics
Replies
3
Views
2K
Back
Top